SteamyTea

I think it is because it is hard to fit it without a lot a time and carefulness. Large steel buildings have roofs that are PU/PIR sandwiched between steels sheets, I think @saveasteading may know more about this.

And find they are governed by the same Laws of Thermodynamics. The real problem is that too many people want to ignore the science.

It really comes down to what you want to achieve with thermal storage. There is energy input types. Input temperatures. Output Temperatures. Output Flow Rates (power). Storage Quantity (energy). Physical size. Overall Mass. Easy of Plumbing. Acceptable Thermal Losses. I have an all electric (E7), small house. My DHW is a 200lt, gravity fed, system that is pumped to the shower. Works fine and has done for 20 years (had to change the old cylinder when it was 20something years old. In all honesty, there is not really going to be much difference, on a small system, whichever type you choose, especially if you only have one energy input type i.e. electricity.

That is the air exiting your dungeon though.

It is an hour earlier here, but it isn't really as I am 7° West of you.

100 kWh.m-2.year-1

My RPi Zero W is still working. It logs and sends the data via the TOR network (did that bit just for fun).

It will be caused by the backfill, so probably very low in reality. It is more a starting point, rather than a finished formula. I am not sure how 'soils' react over time, the N.s will have an affect, but it is probably a differential equation dN/dt of some sort, i.e. as time passes, the movement gets less. One thing about foundations for lightweight buildings is that they may be limited if say, a bungalow is converted to a 2 storey place.

You could try this one, is used in cold forging. Where: Yf = flow stress of the material (Pa) A = cross-section area of the workpiece (m2) r = instantaneous radius of the workpiece (m) h = instantaneous height of the workpiece (m) µ = coefficient of friction between the die and the workpiece

It was not the impact of the 737s that brought down the Twin Towers, it was the softening and associated bucking of the steelwork. As @Gus Potter says, fire is a terrible thing. Is your oven stainless steel? There is a reason that SpaceX use it for rocket bodies, repeatedly.

Too much information; where is the mind bleach.

Oi, newtons. I take it that becomes 0.6 or 0.45m (wide) by 0.2m (high). As that has a mass, (volume times density, so around 250 to 327 kg, or in Roman Catholic up to 3.2 kN) it needs to be added to the static force. Is that right? Also, how how are unusual impact loads dealt with, these can be much, much higher that normal daily loads i.e. a piano can sit for years on the floor, but when Elton John pops around, dumps himself on the stool, it can bring the house down. May account for the extra large footware.

It is quite a problem. Maybe farmers need to contribute more in taxes to counteract the environmental damage they can do.

I am sure there is probably a picture or drawing of the roof in question up here, but is part of the roof timbers going to be open to either a cold side or a warm side, or both even? This can make a difference to the condensation risk. If I remember correctly, placing insulation over the top (exposed to the outside) edge of the timbers is better than placing insulation over the exposed edge on the inside.

Right, did not know that is a convention.

Should that be kN/m²? If I remember correctly, N is a newton, which is mass in kg multiplied by acceleration. So a 100 kg sitting on the ground is: 100 (kg) x 9.81 (m.s-2) =981 N. Spread that over an area of 0.25 m² and you get 3924, so with a bit of rounding, 4kN.m-2.

Basically what I found out when I did my bit of here about it. Lime does absorb some CO2 as the curing takes place, but not sure how much. There are environmentalists and environmentalists. Was interesting spending a year at university with a group of them and seeing where the priorities lay. It is a bit like climate change and politicians, unless the effects are immediate, then it can be ignored. Got to the timber building bit yet?

Well worth listening to this. Answers a lot of misconceptions about cement and concrete. https://www.bbc.co.uk/sounds/play/m0029rqw

Ask @Onoff There is a small amount of info here.

They are. There are structural foams. A lot of early computer cases and enclosures where made from they. Relatively cheap tooling and injection machines, so great for low volume, but good mechanical properties. This has sparked me interest in these polymers again. They fit between 3D printing and full injection moulding. When you get in your car, just think of all the things in it that are foams. Most of the stuff you can see, touch hit, and in an impact. If I was not so tired I would write up a bit more about them, like composite plastics, they are very under used, and more importantly, misunderstood, in the building industry.

The idea is sound. While PU/PIR foams do expand from liquid state, they also warm up. As they cool/cure, they contract a bit (I have mentioned some SIP panels being wavey). This, along with the general aging of the material, may, over time, leave a void. The usual way to overcome much of the contraction, and improve mechanical and thermal stability, is to introduce a filling agent. Melamines are a useful one as they are well understood and improve fire ratings. Other matrixes can be created with long fibres. The biggest problem is long term performance (this can be checked) and chemical leaching (again can be checked). The biggest problem is getting the right people to do the work, processing is everything in the foam industry. A slight variation in temperature or humidity makes a huge difference. We have made 3 'foam sausages' for fire rate testing, same chemicals, same ratios, same machines, same operators, maybe 2 hours apart between 'squirts'. One would pass, 2 may fail. It is down to the reactions between the extra humidity and temperature during the day, this changes the 'bubble' size, which changes the ratio of flame retarders to surface area. Would be an interesting project to be involved in.

Not kept up much this week, it is school holidays, so I am silly busy. But yes, have sniffed most foams in the past, so what was the question?

That is not where the embodied CO2 savings are to be made, there is just not enough of it in a building. The delivery to site will probably produce more CO2. There are a number of ways to reduce CO2, daily energy usage is probably the most important.

Find a new installer. You could consider an in roof fitting systems, they tend to look a lot better anyway.

If they are there to 'help' stabilise the wall in very windy weather, then they are most likely dealing with higher air pressure outside than inside, so compression, mainly. They are probably there for failure mode, than any real contribution to overall structural integrity. And into CWI maybe. Though if your wall is leaking enough water to drip if the bend on a wall tie, then the wall needs sorting, this is not the 1960 after all.