Mon, 25 May 2026 04:21:54 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18434 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18434 Wed, 13 May 2026 05:43:49 +0100 tony
See this picture : - (also further down the thread)

https://share.icloud.com/photos/066qjqEKhBi6whb1qP5FrnWUg

https://www.dropbox.com/scl/fi/15k1oufc1bdnmtthlvbe8/lesson-to-learn.heic?rlkey=sgq0970dw33medi6mk29ceupv&st=vyoi58g9&dl=0

The white streaks running down the Glass are caused by rainwater slightly dissolving the lead, which you can just see above the glass, and taking tiny amounts of lead oxide down the glass. You might think that you could just clean this off easily. You can’t. The lead oxide etches the surface of the glass irreversibly. Ugly and fully preventable.

All architects, glaziers, conservatory manufacturers and in general anyone who specifies glass for use on roofs needs to understand this. And never use lead above glass.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18420 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18420 Fri, 10 Apr 2026 15:32:59 +0100 tony
I’m gonna make some suggestions

1) the client
2) the designer
3) a building physicist - they could be a consultant
4) an engineer
5) an energy assessor
6) a QS ?


? Crack on then ……]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417 Fri, 27 Mar 2026 09:22:41 +0000 tony
In sustainability terms, it seems crazy to build hugely deeper foundations which use an awful lot more concrete and produce additional problems and costs of disposing of the spoil when it may well not have been necessary. I think this approach would be better for the environment too. :-)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18412 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18412 Sat, 07 Mar 2026 08:36:18 +0000 tony
During the 2021/2022 season at DraughtBusters we started to encounter a lot of problems with trickle ventilators. These have been even more of a problem prevalent in 2026.

Some of the problems are : -

Draughty when closed
Insect protection gone or decayed
Wouldn’t or couldn’t close
Householder didn’t know how to open or close them

Draughty when closed.
We found that in a lot of cases draughts were emanating from the trickle vents even when closed. These vents were surprisingly insubstantial and it was rather a shame to find that they were letting in draughts. It would be possible to seal them to the frames to prevent some of the draughts but this would be tricky. If the windows can be used on a ventilate position, i.e. fixed in a secure vent position using the second position on the window handle then we recommend sealing up the trickle ventilators.

Insect protection gone or decayed.
We have identified whole estates where trickle ventilators have lost their insect protection, these are often with ‘over the head’ type ventilator arrangements. The insect grilles become brittle and fall out or are knocked out with window cleaner’s brushes.

Won’t close - this is different from draughty when closed as those do close but a draught enters between the frame and the vent. Some ventilators have plastic clips that hold the vent in place and these can break and the vent flaps about remaining open all the time, others just don’t close and allow draughts all the time even when closed.

Householder can’t open them, we didn’t like this one! There are a lot of different types of trickle ventilators many and varied ways of opening them some push left or right some up and or down, others click open, while others need a sharp but gentle press. It is nor really surprising that some people can’t open them.

Trickle ventilators are the bane of a DraughtBusters life, they are intended to let draughts in, in a controlled way. They are proving themselves to be unfit for purpose. We see ventilation as an active thing, to be controlled by occupants as and when required and a general government directive of ‘one size fits all’ is resulting in draughty homes. We have said before that draughts do too much by way of ventilation when it is windy and not enough when it is calm. Trickle ventilators should now be outlawed in favour of saving energy. Controlled ventilation is what we need.

The adage, ‘build tight ventilate right’ is a very good one, unfortunately trickle vents although the intention was for them to help have turned out to be unhelpful, they cause draughts as highlighted above, do not ventilate right and it will take a lot of work to rectify the situation. Sadly this is a repeat of the same mistake made in the fifties with compulsory through the wall vents in all bedrooms in new homes, DraughtBusters expend a lot of effort blocking those ones up even two generations after they were installed.

The next generation of DraughtBusters will need to spend even more time sorting out leaking trickle ventilators in windows.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17909 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17909 Wed, 26 Jul 2023 12:55:57 +0100 djh
The article it's reporting on - https://www.nature.com/articles/s41467-023-39810-w - uses some apparently heavy duty statistical techniques to suggest it will collapse in 2050-2057 or so but with error bounds that suggest it could happen as early as 2025. Given the importance of the Gulf Stream for the UK climate, it makes me wonder whether the government have any contingency plans to deal with the massive increase in heating energy demand that will result? (Always assuming we've just reached net zero by 2050 of course :devil: )]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18015 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18015 Wed, 08 Nov 2023 22:24:51 +0000 djh https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18014 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18014 Mon, 06 Nov 2023 16:34:14 +0000 tony
Many of us have heard of ‘sick building syndrome’. I am going to talk in this short article about something I’m going to call ‘sick chimney syndrome’. This problem occurs when a chimney is subject to cold conditions at the same time as it gets wet either from saturation or from moisture rising from the house and condensing in the cold part of the chimney above the roof. The upshot of this is that we get a cold tropical rainforest scenario developing in the flue caused by moisture in the house being drawn up the flue by a process of diffusion without the necessity of any air movement. Moisture diffuses through the air and condenses in the brickwork of the chimney or on the capping, add my, on occasions, drip down the flue. Once this process is started, it’s almost impossible to stop it as the evaporation that will occur from the brickwork of the chimney, causes it to be colder than other places nearby, and then that in turn causes further condensation. I call this ‘pumping’ and it is where moisture from the house is literally pumped through structure and into the flue and it then condenses in the brickwork. Moisture moves through the air in a similar way to water in a pipe but no air movement is necessary for the process I am describing.

The result is that the chimney is perpetually wet and doesn’t ever dry out. My recommended solution to this problem is to ventilate the chimney immediately below the capping with two air bricks for each flue on opposite sides of the chimney, so there is a through-draft immediately underneath the chimney capping. Then it is also necessary to ventilate lower down the chimney either in the loft by removing a brick from each flue or immediately above the roofline, one brick per flue should be sufficient.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17979 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17979 Tue, 03 Oct 2023 18:16:53 +0100 djh
https://www.ribaj.com/products/microalgae-grown-limestone-for-concrete-university-of-colorado-boulder

The algae absorb CO2 from the environment as they grow and that is released when the cement is made, using an electric furnace of course. So carbon neutral cement; and if the limestone is also used as aggregate, carbon absorbing concrete.

They talk about cost parity with conventional cement and using 1-2 million acres of land to generate limestone for US building.

Which all sounds very promising. If they just produce limestone perhaps it's also a practical carbon capture method.

What's the gotcha?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17947 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17947 Tue, 12 Sep 2023 11:31:39 +0100 adamsmith
Now I am not sure how to insulate/ detail this. Above the door there is a flitch plate beam door, thus no stud void for PIR like the rest of the timber frame. For this reason, I am particularly concerned with condensation risk in this area. Even though we don’t have the heating on yet there was already condensation on the back of the multi-foil (lucky the VCL seemed to be doing its job and the timber was dry.)

There is only about 25mm depth in the reveals, so I am considering 12mm PIR, then 12mm plasterboard. I am also considering removing the multi-foil from the wall above the door and replacing this with 50mm insulation-backed plaster board, and a new VCL?

Does anyone have any advice on how to insulate door reveals/ heads when there is little space?

Many Thanks]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17810 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17810 Sat, 08 Apr 2023 12:19:53 +0100 billyb_1234
According to the RICS surveyor: " The main issue relates to the roof coverings. They are old (some 90 years I would estimate) and at the end of their useful life expectancy. The photographs give some idea of condition. Patch repairs have been carried out externally in the past. Daylight can be seen in a few places from within the roof void. There is no underfelt. You will need to budget for new coverings, pre-treated battens and vapour-permeable felt".

The survey also suggested it is quite likely that there may have been damp penetration problems with the chimneys, so I was considering the possibility of removing the stacks. In regards to loft insulation, the surveyor said "Some insulation is present within the roof void although this is considered inadequate having regard to current standards. A minimum thickness of 270mm of fibreglass quilt or a similar standard of insulating material should be provided throughout, ensuring that any essential ventilation openings are not obstructed"

The EPC rating is currently band E with potential for band B. The property is my primary residence and my main goal is to reduce energy costs and my carbon footprint.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17822 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17822 Tue, 25 Apr 2023 13:37:11 +0100 djh
I'm not sure what I think of it. Probably low carbon but I'm not sure about how good its performance is. Hint: it's a mixture of cob (i.e. earth and straw) and light-earth (i.e. hemp & clay) techniques.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17397 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17397 Sat, 19 Feb 2022 20:49:03 +0000 tony
There is no evidence that this is dangerous as only a small portion of the plasticiser is lost and only from the outer sheath of the cable. The polystyrene is thinned a tad.

Is anyone aware of a resulting problem?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17309 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17309 Thu, 02 Dec 2021 21:55:27 +0000 tony
For me they are labouring under a misapprehension! The energy that they use is solar energy.

As heat is extracted from the ground, the ground cools and then solar energy gradually tries to bring the temperature back to where it was before. Extraction can slightly alter the equilibrium temperature in extreme cases.

Geothermal energy is heat from hot spring, lava, volcanic activity, mud pools, geysers etc.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17574 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17574 Mon, 19 Sep 2022 22:29:29 +0100 tony
Emulsion paint in plastic tubs: on opening I scrape the paint off the underside of the lid and remix it using an electric mixer on an electric screwdriver, depending on how thick it is in a pot with paint or paint and water, when smooth add to tub and mix in. Wash and clean lid. When there is paint left over the sides of the tub are scraped clean with a broad filling knife and an eggcup full of water tipped on top of the paint before revealing the lid and putting on a shelf.

Tins of water based paints, open clean lid into the paint, mix, use, when done add a spoonful of water, put the lid on using a block of wood. Store on a shelf.

Tins of oil based paint, as above and at the end re-lid and store upside down for a couple of weeks then turn the right way up and store on a shelf. A friend keeps his tins upside down til re-use!

Paint is too expensive to waste.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17522 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17522 Wed, 20 Jul 2022 20:22:40 +0100 djh
Apart from the very obvious observation that timber floors and roof structures burn well, is there anything that could have been done, or that we might consider doing, to reduce or eliminate damage from fires like this? Would sprinklers have made any difference, for example? I know some places such as Australia have rules for building in the bush but would any of those rules transfer and be useful?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17479 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17479 Tue, 31 May 2022 20:25:09 +0100 djh
There's a link in the NS article to another, which links to an accessible journal item https://www.science.org/doi/epdf/10.1126/sciadv.abd7342 about a process for making transparent wood that is quite strong. This also sounds like quite a promising new process.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17313 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17313 Mon, 06 Dec 2021 10:21:28 +0000 Gareth J
Basics;
-South facing, built into a steepish hill
-stone partway, Cobb on top. No mortar, lime or otherwise.
-each leaf of stone gets progressively higher to rest on subsoil, to the point where the northernmost, outer leaf is probably a meter above the southernmost and the field behind rests a foot or so above that.
-roof; of no value.

So, my inclination so far would be to loose the roof and north wall so that a sensible foundation could be put in to let the floor be lowered enough to put in insulation and rebuild the north end with decent damp mitigation and insulation levels. Which is ok by me restoration wise - it would be nicer to restore and retain more originality but the west gable end is concrete block anyway and I fear that in order to do the north end well, without masses more money, including underpinning the that wall, there'll always be damp there and the north end, which isn't visible anyway will obviously benefit the most from being better insulated. And I'll gain space. Plus, I'd be able to get a small swing shovel into the field to make light work of scooping out the concrete floor.

Fine. But what's concerning me is how will a mix match of old/new perform? I could internally insulate the south end a bit with some insulating lime render or something but it'll be minimal compared to the levels achieved on the new bits. Can't really afford the space to use up internally with high levels of IWI and I'd prefer to keep the shape of the old building visible anyway.

So that means inevitability when it's cold, the south wall will be a bit of a heat sink. I'm undecided if that'll be acceptable or odd and uncomfortable? It's such a small space a woodburner should be sufficient to heat it and winter DHW.

Any thoughts appreciated!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15596 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15596 Thu, 01 Mar 2018 15:42:35 +0000 djh
ext temp -2°C and RH 60% implies a dewpoint of -9°C, which given my internal temperature of between 20-21°C implies an internal RH of 12-13%. But the actual RH is 37%. It has been decreasing by maybe a half to one percentage point per day over the past few days. So clearly there is some considerable humidity buffering going on, contrary to thoughts that MVHR means the internal humidity just tracks that outside.

Now I've found https://www.lenntech.com/calculators/humidity/relative-humidity.htm and that suggests that I need internal gains of 250 mL/hour to attain 40% RH or 200 mL/hour for 37% RH at my current ventilation rate of 0.2 ACH.

Does anybody have any idea how to estimate internal gains and/or how to estimate the humidity being supplied by my walls and furniture*?

*Actually, it won't be furniture so much as the wool carpets I expect.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17056 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17056 Thu, 13 May 2021 06:51:49 +0100 tony
https://www.dropbox.com/s/qjs3zx1xr93taod/Wood%20lintels.jpg?dl=0]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16882 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16882 Sun, 10 Jan 2021 17:44:38 +0000 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13794 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=13794 Tue, 10 Nov 2015 22:20:47 +0000 tony
I think they were wrong, did at the time, still do now.

On a recent SIPs build the insulation in the panels started 125mm above finished floor, after a massive fight with the SIPs technical department they allowed us to do something to mitigate this thermal bridge by adding insulation on the outside across the sole plate area.

On the majority of masonry builds insulation still stops at dpc leaving a thermal bridge at the edge of the floor just where you don't want one.

With timber frame insulation starts 97mm above dpc, again a thermal bridge leaving the sole plate prone to pick up condensation. It is the most vulnerable piece of wood in the home apart from any near a shower.

So I ask how far down should wall insulation go? To dpc? Below dpc? To footings? To bottom of foundations?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16391 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16391 Thu, 09 Jan 2020 15:37:59 +0000 djh
https://www.swedishwood.com/publications/list_of_swedish_woods_publications/

They seem to me to be an excellent resource.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16374 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16374 Sun, 29 Dec 2019 10:08:59 +0000 tony
I like this as it talks about kWh/m2/y and gives us numbers where not many do

Monitoring

Pre design]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=10787 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=10787 Sat, 15 Jun 2013 19:25:18 +0100 tony
I simply leave the hot water in the washing up bowl or sink until it has cooled to room temperature in the winter and on cool days, I have solar hot water so tip it to the drain in the summer, the sane with baths.

This is simple and free and we could all do it, there is no necessity to recover the heat from warm water back into water so long as it is made use of it is still heat recovery.

Any container within the heated envelope of a building could be used to recover the heat from baths, showers, washing etc and a simple timed siphon could dump the water when it had cooled, cheap, legal and easy to do.

I know that in other countries there are heat recovery waste pipes but unless regulations change here which is unlikely, then WWHR will remain a very minority sport, I do more than anyone else I know of of it already at zero cost, and as you all know I have no heting system so it irks me to throw heat away .]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16306 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16306 Mon, 28 Oct 2019 23:14:27 +0000 tony
Thoughts please]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16065 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16065 Sun, 10 Mar 2019 12:56:56 +0000 djh
There's an English-language paper at https://www.researchgate.net/publication/329230340_Lime_render_shrinkage_cracks_and_craftsmanship_in_building_restoration which I think may contain some of the material in the thesis, but I haven't received the text of the paper yet.

While searching for the thesis and for anything else about its basic point, I found an excellent summary of limes from Historic Scotland that I think is well worth reading for anybody interested in lime https://www.researchgate.net/publication/264563855_Lime_Mortars_in_Traditional_Buildings_Short_Guide_6

A couple of other more technical things I found for anybody who's still reading are at:

https://www.researchgate.net/publication/278720690_Historic_Mortars
https://www.diva-portal.org/smash/get/diva2:704140/FULLTEXT01.pdf

Oh and FWIW the search I used was 'pdf Lime render, shrinkage cracks and craftsmanship in building restoration']]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16029 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=16029 Wed, 13 Feb 2019 01:53:15 +0000 jonespr1
The wall makeup is from the outside in -> render, blocks, 50mm cavity, Protect TF200 Thermo membrane, 9mm OSB, timber frame with 100mm of PIR insulation, Protect VC Foil Ultra air and vapour membrane, service cavity, plasterboard and plaster.

The builders have started to fit the windows in the outer blocks, over a stone cill. They’ve fitted over a DPC which spans the cavity, the internal membrane has then been folded over the DPC, the cavity isn’t closed. My concern is that any air in the cavity is driven behind the internal membrane, bypassing the insulation. We could close the cavity with cavity closers, but I’m concerned that they still won’t be airtight, particularly the headers.

I would appreciate any advice you can offer on the window detailing, recommended tapes etc…

Robert]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15976 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15976 Sat, 12 Jan 2019 23:26:12 +0000 tony
Lead pumping was a phenomenon well known in Victorian times but little appreciated today. Many Victorian homes had lead box and/or valley gutters. The houses were not as warm as homes would be today but none the less were significantly warmer than outside, the air inside them could carry more moisture in the form of water vapour than the cooler air could outside could, the air was by no means humid but when it came into contact with cool surfaces condensation readily occurred, typically on windows.

There is an unfortunate area where condensation could also take place and this was on the underside of the lead sheets that formed horizontal box or valley gutters, these could get extremely cold and would gather condensation to such an extent that the wooden lining boards underneath this leadwork often became saturated and then started to drip onto the ceilings below making it appear that the roof was leaking. Actually neither the roof nor the valley was leaking but the cold lead was pumping moisture from the house and condensing it rather like the collector inside a dehumidifier does, the difference being that a dehumidifier is designed to capture the condensation and safely store it whereas the valley gutter lining is designed to keep water out from above but has no way of dealing from water that gets under it. The pumping is similar in nature to a siphon and is happening far more than we realise, cold surfaces literally suck moisture from the air In the house and this happens without any air movement and it is not prevented by the presence of the ceiling which is “vapour open”.

Almost every valley gutter that I have ever been involved in repairing showed signs of rot in its boards, more surprising was that this evidence was also present even when the linings were not leaking. This showed that the underside of the lining was getting damp by some other mechanism, presumably from condensation. In general this is not too much of a problem for real wooden boards that are well ventilated but as insulation levels increase, not only will there be less ventilation to carry away the moisture but the valleys will be colder and more often cold than previously as less heat is escaping from the building to help keep them warm.

I think that we will see an increase in the number and severity of problems being caused by “lead pumping” and this will not be restricted to lead linings but also to the underside of other materials used to line or cover roofs and valley gutters.

Tony Cowling — December 2018]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15934 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15934 Tue, 27 Nov 2018 08:11:20 +0000 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15852 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15852 Fri, 07 Sep 2018 12:21:43 +0100 Silky
Have been looking at windows for weeks now, looking at the options for a narrower frame view ( Nordic / Danish / Integral styles etc.. ), i.e. to maximise the visible glass area in retrofit. But something I still don't get ( I think I have forgotten ), what are the potential issues with frame depth ( into the wall )?

e.g.

Typical Inward opening continental windows, i.e. 120mm width 80mm depth
Typical Outward opening continental windows, e.g. 80 mm width 120mm depth

Are deeper profiles problematic for inward opening windows? or something else ?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15820 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15820 Tue, 31 Jul 2018 12:59:57 +0100 gyrogear
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15801&page=1

"(...) maybe with some freezer blocks or bottles of salty water to act as stores of cold?"

This bought my eye, as I am currently configuring my crawlspace as a solar-thermal heat store (using warm air...).
The essential part of the storage will be the concrete structure and (hopefully) the ground. In addition I intend to use a couple of 1000-liter static water batteries (plastic dustbins filled with water).

I have apparently ingested the fact that a tonne of water through one kelvin represents 1.16 kWh of storage capacity.

I am now wondering whether the water ought, in fact to be BRINE - cannot seem to find any info about specific heat of brine via web searches, and my O-level physics was several decades ago...
:shamed:

In addition I have planned for a third storage comprising a 3x3 matrix of nine 240-liter tanks (wheely bins) buried up to their shoulders, the central bin being circulated through a PEX HEX comprising 75 meters of tube inside a hot-air tunnel. The idea being to inject heat into soil... The question is, if BRINE is OK for static storage, would it be OK in a circulated system, or would it corrode the circulator?

Any assistance much appreciated as usual !

gg]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15798 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15798 Fri, 13 Jul 2018 13:23:05 +0100 Silky
I noticed on some professional renovation projects that they have used glass dividing glazing bars. i.e. Windows are made up of several small panes joined with a sub-frame.

I've also now discovered while pricing that this style actually comes in cheaper for e.g. large window divided into 12 sections, in comparison to using 2 larger pieces of glass with the glazing bars glued on externally. Surprise to me.

I can think of another 2 advantages, in terms of ease of ease of installation there are only small pieces of glass to handle and a single piece of damaged glass would be considerably cheaper to replace in the future and there would be no problem of matching the finish of the glazing bars as they would not be changed.

Presumed disadvantage and why I never considered this option before was that the sub-frame would considerably impact the overall u-value of the window, in comparison to using a large piece of glass. Does anyone know if this is true?

And other realted tips?

edit : just adding a link to a picture of the ones I was looking at

https://3.bp.blogspot.com/-FRzj_VT3tcI/WzIETqZhV_I/AAAAAAAAD7E/0xxAyzXknugsJGOHR4eQAbQE7Q6t1paCACLcBGAs/s1600/Marktzentrum%2B%2B06.JPG]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15763 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15763 Thu, 14 Jun 2018 07:58:15 +0100 tony
eg twelve foot span 12/2= 6 + 1 >> use 7x2 joists — ie 47x175 Most houses are built this way sometimes I have seen the mass market builders using half inch sizes to save a bit of Monet]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15564 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15564 Thu, 08 Feb 2018 15:07:41 +0000 djh
https://www.scientificamerican.com/article/stronger-than-steel-able-to-stop-a-speeding-bullet-mdash-it-rsquo-s-super-wood/

https://www.nature.com/articles/d41586-018-01371-0

and the actual article is at https://www.nature.com/articles/nature25476 but behind a paywall :sad:

There's the abstract of an apparently fairly similar but different process at https://www.ncbi.nlm.nih.gov/pubmed/29373784 but again the article is behind a paywall :cry:

Perhaps in a few months the articles will be available and perhaps there'll be a better idea of how practical the work is? :devil:]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15550 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15550 Fri, 02 Feb 2018 23:54:43 +0000 gyrogear
The blocks are 200mm and the wing is generally 250mm, locally wider.
Footing appears to be around 6 inches thick, and sitting on solid bedrock (mudstone).
I'd also like to trim the wing to 250mm (using a cutting wheel) (as depicted by the rebar).

(see photo).

Per F. CHING, the triangle of forces starts at the bottom corner of the footing, and extends outward at a slope. However I do not intend going below the bottom corner of the footing in any case.

Would then recast the footing with high-strength concrete, inside a form board.

Just thought I'd seek comments before going past the point of no return... :shamed:

gg]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15433 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15433 Tue, 05 Dec 2017 12:17:49 +0000 timmywo
I am based in South Poland where the weather can be +30c in summer and -30c in winter. We are in the process of renovating a house and rebuilding the main log cabin section.

We have foundations in and now using the Winter to plan, current topic is wall insulation and space heating requirements.

Please see the SketchUp screen grab of an example wall section, the layers are as follows...

Top OSB
A: Cladding with air gap
B: House wrap, Vapor Permeability OSB > Cladding
C: OSB
D: 25cm ESP insulation, approx R36
C: OSB
G: Internal wrap, Vapor Permeability OSB > Inside
H: Wall finish

Bottom Horizontal Logs (width approx 20cm)
A: Exposed log face with chinking
B: House wrap, Vapor Permeability direction undecided
F: 20cm Mineral Wool Insulation, approx R32
G: Internal wrap, Vapor Permeability Mineral Wool > Inside
H: Wall finish

Roof
I: Metal roofing with air gap
B: House wrap, Vapor Permeability OSB > Cladding
C: OSB
D: 25cm ESP insulation, approx R36
C: OSB
G: Internal wrap, Vapor Permeability OSB > Inside
H: Ceiling finish


My questions for the community...
1. I am undecided on the Log cabin wall if the House Wrap should let vapor out (possible wet logs) or in (thought the Mineral Wool into the house)
2. Now that I know the approx R-value of walls, ceiling, etc - how do I start to calculate the heat requirements for the space for underfloor heating, log burner and HRMV?
3. Any other feedback on the design?

Many thanks in advance,
Tim]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15363 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15363 Tue, 31 Oct 2017 20:56:02 +0000 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15236 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15236 Wed, 16 Aug 2017 20:23:08 +0100 tony
http://www.tonyshouse.readinguk.org/fitting%20a%20bath.htm

Too many baths and showers are still leaking]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15150 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15150 Fri, 23 Jun 2017 17:54:05 +0100 tony
I advocate thinking about it with the inception of the design, in other words before you start thinking about design

Design it in, don't try to add it into a design afterwards]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15103 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15103 Thu, 25 May 2017 15:13:02 +0100 djh
One thing that I found particularly interesting was the technique they used to make the first floor, using a system called Click-Raft. This was invented by the presenter Chris Moller and his team and involves sheets of ply cut by CNC machines and then slotted together to make a rigid lattice panel, which is also quite attractive. It can be used to make entire buildings apparently. Here are some links to more information:

http://click-raft.blogspot.co.uk/
http://cma-u.com/project/click-raft-type-02
http://cma-u.com/project/click-raft-type-03
http://architecturenow.co.nz/articles/cnc-the-new-approach-to-building/]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15102 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15102 Thu, 25 May 2017 11:49:45 +0100 tony
What does it mean now

How tight is tight, in ACH/h at 50Pa is. It 10, 5, 2, less than 1 or some multiple of 0.1? What does tight mean?

Then what is right in terms on ventilation? Depressurising an air tight building with an extract fan? Opening windows, trickle vents, PIV, MVHR, using poor levels of air tightness?

Anyone like to put numbers on ACH and acceptable heat losses due to ventilation?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15001 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15001 Thu, 23 Mar 2017 11:19:06 +0000 gyrogear
I always had suspicions, but painting the mezzanine, it is not a right-angle at the ridge, but 93°

Did some measuring, drew a triangle and resolved it on online calculator:
the south slope has a ridge angle of 48° and the north slope is 45°

Still curious, I notice that 48° corresponds to my latitude: did some more webbing and discovered the notion of "optimizing for winter or summer".

So what was the Architect's intention (1983) : clearly he did not optimize for winter warming with a steep pitch, nor for summer overheating (:shocked:) with a shallow one, so was he being Climate Neutral ?

Curious,:shamed:
N. Brittany

P.S. you can actually get a butchers on the item in question, as I used it elsewhere on here for other reasons...


http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14993&page=1#Item_23]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14429 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14429 Fri, 29 Jul 2016 21:35:34 +0100 tony
Smart plugs (web linked plugs) to control domestic washing machines and freezers.

These would stop freezers working during peak demand periods, on their own these would save us a power station if everyone had one, not impossible.

Similarly not using washing machines during peak demand would greatly help us.

We have a problem meeting peak demand but the system easily copes most of the time.

There could be financial incentives or laws to assist us, either would work.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14960 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14960 Tue, 07 Mar 2017 13:34:23 +0000 ringi
What if the EPS was put on in the normal way without sealing with expanding foam, but the render was still done to a reasonable standard?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14724 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14724 Sun, 27 Nov 2016 00:34:30 +0000 tony
If so then why?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14692 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14692 Wed, 16 Nov 2016 02:42:27 +0000 gyrogear We have formed an association to appeal the project or at least get some say in the design.
Public consultation phase now well under way...
We are in particular interested in getting the building sunk into the ground, in order to limit impacts...

No geotechnical explorations performed (yet) -- early days -- but the area is known to contain gypsum dissolution pockets...

We are wondering to what extent we could use this potential soil status to leverage our argument for deeper foundations (thus a lower roof line).

In particular, how far can we go in "claiming" the advantages of a deep foundation (? diaphragm wall etc.) and earth thrust etc. (or other effects) to offset the (potentially) poor soil conditions?

As you will have gathered, we are none of us civil engineers, so a few links to sites would be of great help, since one day soon we might have to be defending our cause...

Many thanks,

gg]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14682 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14682 Tue, 08 Nov 2016 16:17:05 +0000 djh
The temperature inside this morning was 19.9°C; the temperature outside was just over 2°C; and the internal RH was 45%. And yes, the MVHR was running.

Clearly the indoor humidity isn't the same vapour as in the outside air. I reckon the walls are buffering it.

Or is there another explanation?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14651 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14651 Tue, 25 Oct 2016 23:57:49 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14589 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14589 Mon, 03 Oct 2016 16:23:34 +0100 Silky https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14507 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=14507 Thu, 01 Sep 2016 09:46:22 +0100 tony
1) we should not have leaky homes.
2) we should not throw heat away through fans or through draughts.
3) all new homes should no be built air sealed and with MVHR


On a calm day there is little difference between an air tight home and a leaky one

The benefits of MVHR are more than just the economic ones, air quality improves, heating bills will be lower in all cases, any condensation problems go away.

It has been claimed that MVHR in a leaky home can push humidity into the fabric, this is no more the case that the amounts the home can do for itself without MVHR.]]>