insulation

scatter

I have a dormer house and upstairs the studded walls under the "purloin" have 4 inch insulation ,this i can see when i crawl around the storage area .Now would it be a good idea to staple/nail on that silver foil for extra heat retention ?.I saw this X-foil product ,has anyone used it or similar type before ?

BryanF

scatter wrote: »

I have a dormer house and upstairs the studded walls under the "purloin" have 4 inch insulation ,this i can see when i crawl around the storage area .Now would it be a good idea to staple/nail on that silver foil for extra heat retention ?.I saw this X-foil product ,has anyone used it or similar type before ?

simple answer is NO , you could definately increase the amount of insulation but stay clear of these foil 'pretend insulation' products.

scatter

thanks for replying, but what would you suggest ?

refco

i have dormer and have the frame work along the lenght of it i did the foil thing in the dormer 3 weeks ago best money ive spent you can no longer feel the breeze coming down the hall and when you go up its not like walking into a fridge heat the house in the morning and still feel it in the evening gone from 3 hours a day with heating on to 1 hour

BryanF

scatter wrote: »

thanks for replying, but what would you suggest ?

you

scatter wrote: »

have 4 inch insulation ,this i can see when i crawl around the storage area .

put in 4-12 more of the same or similar (mineral wool/glass, hemp or sheep wool

if you look around the forum, many people have debunked the foil products.
like the poster above said, they will increase air-tightness if sealed correctly, but will not improve thermal performance as much as they claim.

what is your main issue with this crawl space?

• if its air-leakage (drafts) then get an 'airtightness membrane' (type into google)
• if its a lack of heat retention then add more insulation, people are now installing upwards of a ft. of the lower thermal conductivity product types I mentioned above

MicktheMan

scatter wrote: »

I have a dormer house and upstairs the studded walls under the "purloin" have 4 inch insulation ,this i can see when i crawl around the storage area .Now would it be a good idea to staple/nail on that silver foil for extra heat retention ?.I saw this X-foil product ,has anyone used it or similar type before ?

Airtightness, airtightness, airtightness

scatter

I dont have any dormer windows only 4 large veluxes to the rear .There was great talk about the x-foil and similar products .

MicktheMan

scatter wrote: »

I dont have any dormer windows only 4 large veluxes to the rear .

It's not the windows that are the issue generally, it is the dormer roof structure. If the thermal envelope wasn't made air tight originally it can be very difficult to achieve retrospctively.
Add in to the equation such things as recessed lights and access openings to attic space for storage/services etc and you end up with a very good passive stack:eek:

fodda

I used 100mm Kingspan up by the felt (minus 1" gap for air flow) then i put in 50mm "Non-Itch" recycled bottle insulation (like polyester fleece) between the Kingspan and plasterboard slabs. I used this because it isnt supposed to degrade over time like fiberglass. Rhe slabs i used were also Kinspan backed slabs.

Good webpage for explaining on insulation....... www.grow-your-own.ie/insulation.html

Sigur Ros

I used 68mm warmboards a few months ago on the vertical walls in my attic space and am very happy with the results. Definitely helped with retaining heat.