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I'm in the UK which has one of the oldest/energy inefficient housing stocks in Europe. After buying a house built in 1890 I've been made more aware how poor th

I'm in the UK which has one of the oldest/energy inefficient housing stocks in Europe. After buying a house built in 1890 I've been made more aware how poor they can be. After replacing the old secondary glazed windows and replacing the old inefficient gas boiler, I'm moving onto replacing the front and back door, and insulating the suspended floor, walls and room in roof. The walls are solid whinstone about 600mm thick which I'd have expected to be a good insulator but in reality they're a thermal bridge. For generation, I've reserved a spot in Rippleenergy's next co-op turbine [0]. I've been looking into PV/solar thermal/solar battery combinations as well as heat batteries. Sunamp's looks interesting [1] and phase change materials in general. Living in a high latitude (Scotland) the benefit in Winter is more marginal but I'd be happy with simply covering the cost and having peace of mind where the energy came from. PVT panels look interesting if not well-known/scarce. There's so many parts to the answer it seems like energy advisors could be more of a thing in the same way financial advisors are plentiful. [0] https://rippleenergy.com/ https://rippleenergy.com/ [1] https://sunamp.com/thermino-thermal-storage-for-domestic-hot-water/ https://sunamp.com/thermino-thermal-storage-for-domestic-hot...

KaiserPro 5y ago
The next most effective thing to do is External wall insulation. However that'll mean that you'll loose the whinstone look. (unless you pay a _lot_ to get whinstone like shims put on after) The alternative is to have internal wall insulation: https://www.insulationsuperstore.co.uk/product/vacutherm-vacupor-nt-b2-vacuum-insulated-panel-600mm-x-250mm-x-20mm.html https://www.insulationsuperstore.co.uk/product/vacutherm-vac... This is as effective as ~150mm of rockwool, but only 20mm thick. So this can be stuck behind plaster/plasterboard. but its not easy to work with, or widespread yet.
- ricardo81 5y ago
  Yes, it's one of the top recommendations (internal wall insulation) on my EPC and have had a survey. 60mm PIR boards would be used. Turns out I wouldn't have to sacrifice much space but would have to pay a bit extra replacing the cornices. There are some regional grants in the UK that can cover a large portion of the amount. For me, it is £7.5K, with the quote I received at £9K. This would not have covered the kitchen or bathroom. Going by EPC recommendations and numbers alone, I can reduce my energy requirement by about 40%.
  - rogalian 5y ago
    Had to sign up for this. Take extra care to use appropriate materials for a house this age or you'll create more problems than you solve. Solid stone walls need to breathe! Make sure you've spoken with a surveyor specialising in heritage property too. PIR boards are almost certainly unsuitable. https://www.victorian-house.co.uk/ https://www.victorian-house.co.uk/ (be sure to pick up a copy of the Haynes Victorian House manual, it's a gem) https://www.lime.org.uk/community/boards-insulation.html https://www.lime.org.uk/community/boards-insulation.html I'm currently having to undo poor choices of modernisation on a building of the same age, which caused tremendous problems with damp.
    - ricardo81 5y ago
      Thanks for taking the time to sign up. I intend to use rockwool for the floor and roof crawl space. Luckily I have a relative in the field who can share advice. I am conscientious of the condensation issue. There's a company local to me who use hemp boards which are porous. What you say is definitely something to consider given the extent of work involved, and to possibly undo.
    - Dylanfm 5y ago
      Another good resource is https://www.neighbourhoodconstruction.org https://www.neighbourhoodconstruction.org e.g their page on Thermal Envelope > Bio aggregate https://www.neighbourhoodconstruction.org/bio-aggregate/ https://www.neighbourhoodconstruction.org/bio-aggregate/
  - markvdb 5y ago
    Be super careful internally insulating an old house. This can cause _a lot_ of humidity problems if not done _exactly_ right. Very often, there is no way to do it exactly right! I would recommend you to consider breathable internal insulation materials, combined with breathable finish layers of course! Some hints. Roof (or attic floor) insulation is the most important. I imagine those have been done properly already. Walls. There's industrial products for walls, like Xella Multipor. You may also want to have a look at eco products, especially if working on the place yourself. Hempcrete is a fairly forgiving material that works rather well for this purpose. Rather expensive to have it installed, but easy to do yourself. Ground floors. Have a look at foam glass [0] insulation. It both stabilises and insulates, is moisture and fire proof, not horribly expensive and saves you from having to put in a layer of concrete. Not super well known yet, but growing in popularity. A wonderful material and super easy and forgiving to work with. A no-brainer really in many cases... [0] https://en.wikipedia.org/wiki/Foam_glass https://en.wikipedia.org/wiki/Foam_glass
- lbriner 5y ago
  An easier solution is plasterboard already bonded to PIR or XPS. The XPS is cheaper and I don't think it will make a massive difference depending on all the other challenges like windows and doors. You can simply stick this to existing walls with adhesive foam and then dry-line or skim the boards afterwards. To do it well, though, you will often need to cut out/remove any laminate flooring so the boards can meet the floor and they won't do anything about leakage between floors, which can be significant.
  - KaiserPro 5y ago
    > plasterboard already bonded to PIR As you point out they are normally ~25mm or so of EPS/XPS. which doesn't do _much_, especially compared to 600mm of stone. Plus XPS is pretty flammable, so with electricity cables sandwiched between it, its not a great thing to have inside the house.
- bainsfather 5y ago
  I followed your link, but am confused and/or doubtful: how do you replace 150mm of rockwool with 20mm of anything other than a good vacuum? It says that they are 'very low internal pressure' - but if it contains any kind of gas (which i presume it must do - air if nothing else) then the conductivity does not depend on pressure until the mean-free-path has increased to be > the width of the container. Is this product real? What is it about the physics that I am not understanding? And how do you maintain the 'very low internal pressure' over the decades that you will need it for? Thanks.
  - coryrc 5y ago
    It is a good vacuum. They work but are expensive and a single nail destroys the whole panel, but maybe cheaper than the loss of floor space.
  - KaiserPro 5y ago
    From what I've seen, its basically a honeycomb with a thick plastic coated foil to act as an atmospheric barrier. I came across it from a number of sites, but I've not managed to get any samples yet. > And how do you maintain the 'very low internal pressure' over the decades that you will need it for? now thats a million dollar question. I don't know.
  - londons_explore 5y ago
    > conductivity does not depend on pressure I think it might be fumed silica aerogel at about 0.1 bar. This paper describes the use of the same material for building insulation: https://www.researchgate.net/figure/a-The-thermal-conductivity-of-air-as-a-function-of-the-air-pressure-and-the-average_fig2_281970746 https://www.researchgate.net/figure/a-The-thermal-conductivi... I suspect the key issue will be maintaining that low pressure for the ~100 year lifespan of the building. Perhaps future versions will come with micro pumps so that once per year the pressure can be pumped back down to 0.1 bar. Looks like for about a dollar you can buy a little 3 volt vacuum pump. One per panel out to do a decent job.
  - chipsa 5y ago
    https://en.wikipedia.org/wiki/Vacuum_insulated_panel https://en.wikipedia.org/wiki/Vacuum_insulated_panel Looks like the thing. So, yeah, very good vacuum. It's apparently decades for the lifespan, but much of it boils down to the materials being used.
Mvandenbergh 5y ago
I work on energy systems modelling and how domestic thermal performance interfaces with that - the UK has not just "one of the oldest in Europe" it actually has the oldest in the world. Many European countries had a lot more post WWII construction so at least have cavity walls (even if in many cases not filled until later).
- cjrp 5y ago
  My understanding was that cavities should actually not be filled, since they allow water to drain out. Is that incorrect?
  - Mvandenbergh 5y ago
    The issue is will the cavity system allow water to penetrate to the inner leaf which is bad and will cause internal dampness. Cavities can be carefully partially filled with some type of insulation which allows the water soaking through the brick to evaporate and drain back out. The standard technique is to use blown in EPS beads which allow for drainage downwards, reducing the chance that any water loading will make it through the insulation layer and to the inner leaf of the wall. Problems with cavity insulation are often caused by: -Treating walls which have a large amount of debris in the cavity, leading to water bridging -Over-filling cavities which also leads to water bridging -Treating walls with very large amounts of rain exposure, especially to driving rain for extended periods of time since this will lead to saturation of the cavity insulation system which may be unable to dry for months at a time. These walls should be externally insulated and clad instead. In the UK context for example, houses in Wales and parts of the English South coast, the whole Southwest, the East of Scotland, and most of NI are in zones 3 and 4 in terms of wind driven rain exposure. In zone 3 and 4, installers are required to carry out an assessment of site conditions and of cavity thickness as well as exterior wall finish. Older houses might have 50mm cavities, new properties often have 100mm or 150mm cavities. Obviously that reduces the changes of water soaking through. Approved Document C allows a full fill of insulation for a 75mm cavity on a fully rendered wall and on a 50mm cavity if clad with rain impervious material but requires 150mm for bare masonry.

KaiserPro 5y ago

The next most effective thing to do is External wall insulation. However that'll mean that you'll loose the whinstone look. (unless you pay a _lot_ to get whinstone like shims put on after) The alternative is to have internal wall insulation: https://www.insulationsuperstore.co.uk/product/vacutherm-vacupor-nt-b2-vacuum-insulated-panel-600mm-x-250mm-x-20mm.html https://www.insulationsuperstore.co.uk/product/vacutherm-vac... This is as effective as ~150mm of rockwool, but only 20mm thick. So this can be stuck behind plaster/plasterboard. but its not easy to work with, or widespread yet.

ricardo81 5y ago
Yes, it's one of the top recommendations (internal wall insulation) on my EPC and have had a survey. 60mm PIR boards would be used. Turns out I wouldn't have to sacrifice much space but would have to pay a bit extra replacing the cornices. There are some regional grants in the UK that can cover a large portion of the amount. For me, it is £7.5K, with the quote I received at £9K. This would not have covered the kitchen or bathroom. Going by EPC recommendations and numbers alone, I can reduce my energy requirement by about 40%.
- rogalian 5y ago
  Had to sign up for this. Take extra care to use appropriate materials for a house this age or you'll create more problems than you solve. Solid stone walls need to breathe! Make sure you've spoken with a surveyor specialising in heritage property too. PIR boards are almost certainly unsuitable. https://www.victorian-house.co.uk/ https://www.victorian-house.co.uk/ (be sure to pick up a copy of the Haynes Victorian House manual, it's a gem) https://www.lime.org.uk/community/boards-insulation.html https://www.lime.org.uk/community/boards-insulation.html I'm currently having to undo poor choices of modernisation on a building of the same age, which caused tremendous problems with damp.
  - ricardo81 5y ago
    Thanks for taking the time to sign up. I intend to use rockwool for the floor and roof crawl space. Luckily I have a relative in the field who can share advice. I am conscientious of the condensation issue. There's a company local to me who use hemp boards which are porous. What you say is definitely something to consider given the extent of work involved, and to possibly undo.
  - Dylanfm 5y ago
    Another good resource is https://www.neighbourhoodconstruction.org https://www.neighbourhoodconstruction.org e.g their page on Thermal Envelope > Bio aggregate https://www.neighbourhoodconstruction.org/bio-aggregate/ https://www.neighbourhoodconstruction.org/bio-aggregate/
- markvdb 5y ago
  Be super careful internally insulating an old house. This can cause _a lot_ of humidity problems if not done _exactly_ right. Very often, there is no way to do it exactly right! I would recommend you to consider breathable internal insulation materials, combined with breathable finish layers of course! Some hints. Roof (or attic floor) insulation is the most important. I imagine those have been done properly already. Walls. There's industrial products for walls, like Xella Multipor. You may also want to have a look at eco products, especially if working on the place yourself. Hempcrete is a fairly forgiving material that works rather well for this purpose. Rather expensive to have it installed, but easy to do yourself. Ground floors. Have a look at foam glass [0] insulation. It both stabilises and insulates, is moisture and fire proof, not horribly expensive and saves you from having to put in a layer of concrete. Not super well known yet, but growing in popularity. A wonderful material and super easy and forgiving to work with. A no-brainer really in many cases... [0] https://en.wikipedia.org/wiki/Foam_glass https://en.wikipedia.org/wiki/Foam_glass
lbriner 5y ago
An easier solution is plasterboard already bonded to PIR or XPS. The XPS is cheaper and I don't think it will make a massive difference depending on all the other challenges like windows and doors. You can simply stick this to existing walls with adhesive foam and then dry-line or skim the boards afterwards. To do it well, though, you will often need to cut out/remove any laminate flooring so the boards can meet the floor and they won't do anything about leakage between floors, which can be significant.
- KaiserPro 5y ago
  > plasterboard already bonded to PIR As you point out they are normally ~25mm or so of EPS/XPS. which doesn't do _much_, especially compared to 600mm of stone. Plus XPS is pretty flammable, so with electricity cables sandwiched between it, its not a great thing to have inside the house.
bainsfather 5y ago
I followed your link, but am confused and/or doubtful: how do you replace 150mm of rockwool with 20mm of anything other than a good vacuum? It says that they are 'very low internal pressure' - but if it contains any kind of gas (which i presume it must do - air if nothing else) then the conductivity does not depend on pressure until the mean-free-path has increased to be > the width of the container. Is this product real? What is it about the physics that I am not understanding? And how do you maintain the 'very low internal pressure' over the decades that you will need it for? Thanks.
- coryrc 5y ago
  It is a good vacuum. They work but are expensive and a single nail destroys the whole panel, but maybe cheaper than the loss of floor space.
- KaiserPro 5y ago
  From what I've seen, its basically a honeycomb with a thick plastic coated foil to act as an atmospheric barrier. I came across it from a number of sites, but I've not managed to get any samples yet. > And how do you maintain the 'very low internal pressure' over the decades that you will need it for? now thats a million dollar question. I don't know.
- londons_explore 5y ago
  > conductivity does not depend on pressure I think it might be fumed silica aerogel at about 0.1 bar. This paper describes the use of the same material for building insulation: https://www.researchgate.net/figure/a-The-thermal-conductivity-of-air-as-a-function-of-the-air-pressure-and-the-average_fig2_281970746 https://www.researchgate.net/figure/a-The-thermal-conductivi... I suspect the key issue will be maintaining that low pressure for the ~100 year lifespan of the building. Perhaps future versions will come with micro pumps so that once per year the pressure can be pumped back down to 0.1 bar. Looks like for about a dollar you can buy a little 3 volt vacuum pump. One per panel out to do a decent job.
- chipsa 5y ago
  https://en.wikipedia.org/wiki/Vacuum_insulated_panel https://en.wikipedia.org/wiki/Vacuum_insulated_panel Looks like the thing. So, yeah, very good vacuum. It's apparently decades for the lifespan, but much of it boils down to the materials being used.

Mvandenbergh 5y ago

I work on energy systems modelling and how domestic thermal performance interfaces with that - the UK has not just "one of the oldest in Europe" it actually has the oldest in the world. Many European countries had a lot more post WWII construction so at least have cavity walls (even if in many cases not filled until later).

cjrp 5y ago
My understanding was that cavities should actually not be filled, since they allow water to drain out. Is that incorrect?
- Mvandenbergh 5y ago
  The issue is will the cavity system allow water to penetrate to the inner leaf which is bad and will cause internal dampness. Cavities can be carefully partially filled with some type of insulation which allows the water soaking through the brick to evaporate and drain back out. The standard technique is to use blown in EPS beads which allow for drainage downwards, reducing the chance that any water loading will make it through the insulation layer and to the inner leaf of the wall. Problems with cavity insulation are often caused by: -Treating walls which have a large amount of debris in the cavity, leading to water bridging -Over-filling cavities which also leads to water bridging -Treating walls with very large amounts of rain exposure, especially to driving rain for extended periods of time since this will lead to saturation of the cavity insulation system which may be unable to dry for months at a time. These walls should be externally insulated and clad instead. In the UK context for example, houses in Wales and parts of the English South coast, the whole Southwest, the East of Scotland, and most of NI are in zones 3 and 4 in terms of wind driven rain exposure. In zone 3 and 4, installers are required to carry out an assessment of site conditions and of cavity thickness as well as exterior wall finish. Older houses might have 50mm cavities, new properties often have 100mm or 150mm cavities. Obviously that reduces the changes of water soaking through. Approved Document C allows a full fill of insulation for a 75mm cavity on a fully rendered wall and on a 50mm cavity if clad with rain impervious material but requires 150mm for bare masonry.