External Insulation & Windows

Duffers11

Hi, will be applying external insulation to new build once the roof is complete but in order to get the exact window measurements and order, we want to apply perimeter insulation, prob 20mm around the window opes. Our window supplier said that the insulation that the window/door sits on would need to be different than rest to take the weight/prevent movement. Cant seem to find a product like this at all. Would anybody know where I could source this. Only needs to be 20-25mm purely to meet the outer 150mm insulation and prevent cold bridge! Any supplier recommendations greatly appreciated!! Pm if necessary. Thanks

braftery

Do you mean you want the window units to sit on insulation ?

sydthebeat

Duffers11 wrote: »

Hi, will be applying external insulation to new build once the roof is complete but in order to get the exact window measurements and order, we want to apply perimeter insulation, prob 20mm around the window opes. Our window supplier said that the insulation that the window/door sits on would need to be different than rest to take the weight/prevent movement. Cant seem to find a product like this at all. Would anybody know where I could source this. Only needs to be 20-25mm purely to meet the outer 150mm insulation and prevent cold bridge! Any supplier recommendations greatly appreciated!! Pm if necessary. Thanks

the doors / windows should not sit on any insulation. They should be hung from fixings tied back to the block wall. The windows and doors should actually be installed before the external insulation, but fixed to be proud of the block wall and within the insulation leaf.

The block wall should have been build + designed to take whatever weight it is supposed to support.

braftery

+1 Syd ... I was waiting for confirmation before I outlined the same points !

sas

Window ready for EWI

Duffers11

Hi, I managed to source a 6mm board that is going to applied around the ope that is load bearing which the window sits in to and fixed to wall. This way there is continual insulation to which we can bring up the external to meet.

Duffers11

And the walls have been constructed to take the additional weight where the fixings will be placed.

sydthebeat

Duffers11 wrote: »

Hi, I managed to source a 6mm board that is going to applied around the ope that is load bearing which the window sits in to and fixed to wall. This way there is continual insulation to which we can bring up the external to meet.

duffers, are you windows fixed in the same manner as the pic above? ie proud of the block wall?
a pic from you would be a huge help

i dont understand why another material is required to to take the weight of the window.... can you explain please.

if your window is located 'within' the insulation leaf, then its continuously insulated anyway.

braftery

There are insulating materials that can take large load, but this is normally a spread load.

Windows usually require packers, etc to insure they are true, level and plumb, and it is essential that they are installed as such in order for them to continueto function properly over time. These packers will be point load on any soft surface (mind you 6mm is pretty thin !), and it will mean the packers, etc will not do the job they are designed too.

Like sydthebeat, I am quite confused by your method and have never come across it before. I would love to understand why you are using this method and not installing as shown in the picture above ?