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Hi Everybody
We have a small three storey, two bedroomed terrace house that faces SSW. In summer the main bedroom on the south side of the top floor gets way too warm. As a solution I am proposing to line the inside of the bedroom on the exterior wall sides plus the cathedral ceiling with Aerogel Board (10mm Aerogell bonded to 9mm of magnesium board). My potential contractor warned that this would be of interest to the Building Regulations folk and he was right. I have had a couple of very helpful emails from them but they say that I need to have the U value for the exterior wall and for the cathedral ceiling.
I have attached a rought drawing to provide a cross section of the bedroom. The second drawing shows my calculations of the elements in the construction. These are in part hypothesised. The house was built in the late 1980s or early 1990s. The wall construction of medium density block, insulation batt (probably Kingspan type), air space, then brick is right as I saw that when the central heating boiler flue was changed. The dimensions of the insulation and air gap are derived knowing that the total wall thickness is 300mm and the bricks and blocks are 100mm wide each.. A similar approach was used for the cathedral ceiling. From an open Velux it was possible to measure the roof thickness as 180mm. The roof timbers are 92mm deep while the tile and batten must be at least 40mm leaving about 50mm for insulated plaster boaard. The latter is probably Kindspan type again as investigation with my endoscope showed nothing fibrous which whould have been fibreglass.
So my question is whether my hypothesised dimensions look right and then, if so, what would the U value of the exteriaor wall and the cathedral ceiling be?
Your comments and calculations would be gratefully received
Regards
Pete
We have a small three storey, two bedroomed terrace house that faces SSW. In summer the main bedroom on the south side of the top floor gets way too warm. As a solution I am proposing to line the inside of the bedroom on the exterior wall sides plus the cathedral ceiling with Aerogel Board (10mm Aerogell bonded to 9mm of magnesium board). My potential contractor warned that this would be of interest to the Building Regulations folk and he was right. I have had a couple of very helpful emails from them but they say that I need to have the U value for the exterior wall and for the cathedral ceiling.
I have attached a rought drawing to provide a cross section of the bedroom. The second drawing shows my calculations of the elements in the construction. These are in part hypothesised. The house was built in the late 1980s or early 1990s. The wall construction of medium density block, insulation batt (probably Kingspan type), air space, then brick is right as I saw that when the central heating boiler flue was changed. The dimensions of the insulation and air gap are derived knowing that the total wall thickness is 300mm and the bricks and blocks are 100mm wide each.. A similar approach was used for the cathedral ceiling. From an open Velux it was possible to measure the roof thickness as 180mm. The roof timbers are 92mm deep while the tile and batten must be at least 40mm leaving about 50mm for insulated plaster boaard. The latter is probably Kindspan type again as investigation with my endoscope showed nothing fibrous which whould have been fibreglass.
So my question is whether my hypothesised dimensions look right and then, if so, what would the U value of the exteriaor wall and the cathedral ceiling be?
Your comments and calculations would be gratefully received
Regards
Pete
