Home |
Search |
Today's Posts |
|
UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
|
#1
|
|||
|
|||
Cavity wall insulation
I'm looking to add insulation to the cavity in a conservatory wall during
building but I'm not clear what thickness of material to use. I had assumed that it would be necessary/best to fill the cavity but investigations suggest that less than 1/3 this thickness seems to be generally used. Is one option a false economy or the other a waste of money? NB We are intending to use the room in all seasons. -- John Cartmell john@ followed by finnybank.com 0845 006 8822 Qercus magazine FAX +44 (0)8700-519-527 www.finnybank.com Qercus - the best guide to RISC OS computing |
#2
|
|||
|
|||
On Fri, 22 Jul 2005 21:09:32 +0100, John Cartmell
wrote: I'm looking to add insulation to the cavity in a conservatory wall during building but I'm not clear what thickness of material to use. I had assumed that it would be necessary/best to fill the cavity but investigations suggest that less than 1/3 this thickness seems to be generally used. Is one option a false economy or the other a waste of money? NB We are intending to use the room in all seasons. Yes it does make sense to fill it. Insulating foam or insulating glass fibre or Rockwool batts are typical. However, if it is a dwarf wall - say up to about 6 courses of bricks - then the glass will represent the bulk of the heat loss anyway. It is worth going for low emissivity glass with the double glazing space gas filled. Another thing that should be included is to insulate the floor. Styrofoam is used for this, I believe typically of 100mm thickness, and is quite cheap. -- ..andy To email, substitute .nospam with .gl |
#3
|
|||
|
|||
In article , Andy Hall
wrote: On Fri, 22 Jul 2005 21:09:32 +0100, John Cartmell wrote: I'm looking to add insulation to the cavity in a conservatory wall during building but I'm not clear what thickness of material to use. I had assumed that it would be necessary/best to fill the cavity but investigations suggest that less than 1/3 this thickness seems to be generally used. Is one option a false economy or the other a waste of money? NB We are intending to use the room in all seasons. Yes it does make sense to fill it. Insulating foam or insulating glass fibre or Rockwool batts are typical. Thanks. It made sense to me but every (commercially built) one that I checked seemed to have used something like 1-2cm thick foam. Cheap? -- John Cartmell john@ followed by finnybank.com 0845 006 8822 Qercus magazine FAX +44 (0)8700-519-527 www.finnybank.com Qercus - the best guide to RISC OS computing |
#4
|
|||
|
|||
On Fri, 22 Jul 2005 22:46:28 +0100, John Cartmell
wrote: In article , Andy Hall wrote: On Fri, 22 Jul 2005 21:09:32 +0100, John Cartmell wrote: I'm looking to add insulation to the cavity in a conservatory wall during building but I'm not clear what thickness of material to use. I had assumed that it would be necessary/best to fill the cavity but investigations suggest that less than 1/3 this thickness seems to be generally used. Is one option a false economy or the other a waste of money? NB We are intending to use the room in all seasons. Yes it does make sense to fill it. Insulating foam or insulating glass fibre or Rockwool batts are typical. Thanks. It made sense to me but every (commercially built) one that I checked seemed to have used something like 1-2cm thick foam. Cheap? Probably. -- ..andy To email, substitute .nospam with .gl |
#5
|
|||
|
|||
On Fri, 22 Jul 2005 21:09:32 +0100, John Cartmell
wrote: I'm looking to add insulation to the cavity in a conservatory wall during building but I'm not clear what thickness of material to use. I had assumed that it would be necessary/best to fill the cavity but investigations suggest that less than 1/3 this thickness seems to be generally used. Is one option a false economy or the other a waste of money? NB We are intending to use the room in all seasons. From whant I found when I built my house, u have 2 choices 100mm full-fill cavity bats, they must be the "full fill" type. OR 50mm kingspan, held against inner leaf. Both have the same U value. The kangspan can not be used as "full fill". The floor, you can put 100mm kingspan in. Having said this, the windows are gonna be a much bigger heat loss/gain problem. Rick |
#6
|
|||
|
|||
"Rick" wrote in message ... On Fri, 22 Jul 2005 21:09:32 +0100, John Cartmell wrote: I'm looking to add insulation to the cavity in a conservatory wall during building but I'm not clear what thickness of material to use. I had assumed that it would be necessary/best to fill the cavity but investigations suggest that less than 1/3 this thickness seems to be generally used. Is one option a false economy or the other a waste of money? NB We are intending to use the room in all seasons. From whant I found when I built my house, u have 2 choices 100mm full-fill cavity bats, they must be the "full fill" type. OR 50mm kingspan, held against inner leaf. Both have the same U value. The kangspan can not be used as "full fill". The floor, you can put 100mm kingspan in. Having said this, the windows are gonna be a much bigger heat loss/gain problem. It all adds up. The floor is a large area and added to the dwarf walls a reasonable percentage of the overall area, so worth insulation well. If the conservatory is against the outside wall of the house the conservatory acts as an extra layer of insulation on that wall. As no rain will penetrate this section outside wall, full filling the house wall against the conservatory is a good thing. The problem is getting inside the cavity, so a spray in foam would need to be used. |
#7
|
|||
|
|||
On Sat, 23 Jul 2005 10:38:21 +0100, "Doctor Drivel"
wrote: It all adds up. The floor is a large area and added to the dwarf walls a reasonable percentage of the overall area, so worth insulation well. If the conservatory is against the outside wall of the house the conservatory acts as an extra layer of insulation on that wall. As no rain will penetrate this section outside wall, full filling the house wall against the conservatory is a good thing. The problem is getting inside the cavity, so a spray in foam would need to be used. ??? You can insert insulating batts or Celotex while the wall is being built. -- ..andy To email, substitute .nospam with .gl |
#8
|
|||
|
|||
"Andy Hall" wrote in message ... On Sat, 23 Jul 2005 10:38:21 +0100, "Doctor Drivel" wrote: It all adds up. The floor is a large area and added to the dwarf walls a reasonable percentage of the overall area, so worth insulation well. If the conservatory is against the outside wall of the house the conservatory acts as an extra layer of insulation on that wall. As no rain will penetrate this section outside wall, full filling the house wall against the conservatory is a good thing. The problem is getting inside the cavity, so a spray in foam would need to be used. ??? You can insert insulating batts or Celotex while the wall is being built. The existing house wall. Duh! |
#9
|
|||
|
|||
On Sat, 23 Jul 2005 11:31:07 +0100, "Doctor Drivel"
wrote: "Andy Hall" wrote in message .. . On Sat, 23 Jul 2005 10:38:21 +0100, "Doctor Drivel" wrote: It all adds up. The floor is a large area and added to the dwarf walls a reasonable percentage of the overall area, so worth insulation well. If the conservatory is against the outside wall of the house the conservatory acts as an extra layer of insulation on that wall. As no rain will penetrate this section outside wall, full filling the house wall against the conservatory is a good thing. The problem is getting inside the cavity, so a spray in foam would need to be used. ??? You can insert insulating batts or Celotex while the wall is being built. The existing house wall. Duh! The question was about the new wall not the existing. Try to keep up. -- ..andy To email, substitute .nospam with .gl |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Cavity insulation, how do you know if you have it? | UK diy | |||
insulation - behind wall slats? | Home Repair | |||
Dropping a cable through cavity wall. | UK diy | |||
insulating a wall | UK diy | |||
HELP: vertical foundation crack in new construction | Home Repair |