Have been on a bit of a deep dive in terms of Building Regulations lately. Its really eye opening how much is covered (and how much people probably don't worry about it).
I have a Victorian terrace. The whole thing, front and back, sadly caked in cement render. At the back of the outrigger there is the upstairs bathroom wall with an old chimney running up the back. A lean-to has been added at the bottom, so at the ground floor level the former external wall has become internal. The render around the chimney stack was in a very poor state and was letting water into the chimney. This was a potential contributor to general damp in the old chimney and a cold spot in the bathroom on the internal side which is always damp.
The wall is a total of about 3x3m. For all the reasons above, last year I had the cement render taken off and re-rendered in lime. As they got to the chimney stack the bricks were really deteriorated, so the stack (which is only small) was left unrendered but has now been nicely pointed and flaunched with lime with some replacement bricks. The rest of the wall was rendered at the time.
At the time I did look through Part L of the building regs. My interpretation was that it was less than 50% of the rear elevation (i.e. if you look at the back of the house then this wall makes up less than 50% of all the walls that you can see when looking straight ahead at the house). I now realise that that may not be the correct interpretation, and perhaps the bathroom wall was itself a single thermal element and in which case I actually rendered 100% of it. So question 1) does anyone know what counts as a 'elevation' when the house isn't just a square box? The example in the Part L is a box shaped house and it doesn't clearly set out how to interpret things with houses where bits stick out.
I also did it because the cement render needed repair and damage was being caused by it, and thought that there was a dispensation that you could use appropriate materials that won't cause further damage to solid walled buildings. A dry(ing) wall has a better U Value than a damp wall, so it would be an improvement in that regard. I didn't want to use external wall insulation because of the risk of condensation if it was done badly, and also because the detailing around the chimney stack and lean-to would be complicated. If installed badly this could have lead to water ingress. Finally, the payback time for any of these things (lime or insulated render or cement or whatever) will be greater than 15 years. Its too small a wall relative to the cost of scaffold and labour for it to actually save me money. That isn't why I did it.
Anyway, long story short. I now need a Building Control Officer to come and hopefully sign off some mundane things and I'm worried they might ask me about this render. I feel like I have/had a very good argument for using lime, and its only 9m2 ish of the house. I'm also making other thermal improvements in ways that will probably have a greater benefit and be less risky. However, I didn't have this conversation with them at the time because, for the reasons above, I thought it was exempt.
Goodness knows how many people just get their houses re-rendered, lime or otherwise, without giving this a second thought. But it does make me edgy. Any thoughts or experience on this kind of thing?
I have a Victorian terrace. The whole thing, front and back, sadly caked in cement render. At the back of the outrigger there is the upstairs bathroom wall with an old chimney running up the back. A lean-to has been added at the bottom, so at the ground floor level the former external wall has become internal. The render around the chimney stack was in a very poor state and was letting water into the chimney. This was a potential contributor to general damp in the old chimney and a cold spot in the bathroom on the internal side which is always damp.
The wall is a total of about 3x3m. For all the reasons above, last year I had the cement render taken off and re-rendered in lime. As they got to the chimney stack the bricks were really deteriorated, so the stack (which is only small) was left unrendered but has now been nicely pointed and flaunched with lime with some replacement bricks. The rest of the wall was rendered at the time.
At the time I did look through Part L of the building regs. My interpretation was that it was less than 50% of the rear elevation (i.e. if you look at the back of the house then this wall makes up less than 50% of all the walls that you can see when looking straight ahead at the house). I now realise that that may not be the correct interpretation, and perhaps the bathroom wall was itself a single thermal element and in which case I actually rendered 100% of it. So question 1) does anyone know what counts as a 'elevation' when the house isn't just a square box? The example in the Part L is a box shaped house and it doesn't clearly set out how to interpret things with houses where bits stick out.
I also did it because the cement render needed repair and damage was being caused by it, and thought that there was a dispensation that you could use appropriate materials that won't cause further damage to solid walled buildings. A dry(ing) wall has a better U Value than a damp wall, so it would be an improvement in that regard. I didn't want to use external wall insulation because of the risk of condensation if it was done badly, and also because the detailing around the chimney stack and lean-to would be complicated. If installed badly this could have lead to water ingress. Finally, the payback time for any of these things (lime or insulated render or cement or whatever) will be greater than 15 years. Its too small a wall relative to the cost of scaffold and labour for it to actually save me money. That isn't why I did it.
Anyway, long story short. I now need a Building Control Officer to come and hopefully sign off some mundane things and I'm worried they might ask me about this render. I feel like I have/had a very good argument for using lime, and its only 9m2 ish of the house. I'm also making other thermal improvements in ways that will probably have a greater benefit and be less risky. However, I didn't have this conversation with them at the time because, for the reasons above, I thought it was exempt.
Goodness knows how many people just get their houses re-rendered, lime or otherwise, without giving this a second thought. But it does make me edgy. Any thoughts or experience on this kind of thing?
