Perimeter Insulation Limits

BarneyMc

Is there a practical limit to the thickness of perimeter insulation that should be installed? I'm not 'slabbing' my walls and have used Quinnlites around the bases of all walls. My floor insulation makeup will be 2x70mm K3/PIR. Would using these 70mm boards for perimeter insulation be overkill?

sydthebeat

Yes. Think of the practicality of the floor covering over, such as tiles etc

25 would be sufficient if you have dry quinnlites in the rising walls

Czhornet

Why dont you slab the external wall with the insulated slab, great job and would highly recommend it. All the heat stays in the room. 140mm floor insulation sounds like alot, heat rises you know.

BarneyMc

Czhornet wrote: »

Why dont you slab the external wall with the insulated slab, great job and would highly recommend it. All the heat stays in the room. 140mm floor insulation sounds like alot, heat rises you know.

I've a 250mm cavity and would rather use my walls as a thermal store to maintian an even temp in the room. Warm air rises, heat travels in all directions.

Czhornet

have you insulation of any kind in the cavity?
coldness from outside will cool the outer leaf, cool the air in the cavity (its not that much of an insulator) and cool the inner block. I put down under floor heating and the screed acts as a thermal store in my house. your block will always feel cold to the touch with no insulation...

sydthebeat

Czhornet wrote: »

coldness from outside will cool the outer leaf, cool the air in the cavity (its not that much of an insulator) and cool the inner block..

errmmmm

theres 250mm of insulation between both leafs, to stop that happening.


Internal insulation has been shown over and over to be a sub standard method for a new build.

hexosan

I've 200mm eps in the floor and I'm using 50mm strips for the perimeter insulation.

BarneyMc

hexosan wrote: »

I've 200mm eps in the floor and I'm using 50mm strips for the perimeter insulation.

How does 50mm strip insulation work as surely you'll have to tile/floor over some of this as your skirting board won't cover the 50mm?

hexosan

Plaster coat on the walls and the skirting will take up at least half the 50mm floor will only overhang it my an inch max. And it's not like anyone will be able to walk within an inch of the wall.

BarneyMc

hexosan wrote: »

Plaster coat on the walls and the skirting will take up at least half the 50mm floor will only overhang it my an inch max. And it's not like anyone will be able to walk within an inch of the wall.

Seems reasonable and not expensive to do. I assume ALL walls should get this treatment?

hexosan

I assumed it's only necessary on the external walls. But it's not that difficult to do it on all walls.

Strolling Bones

hexosan wrote: »

I assumed it's only necessary on the external walls. But it's not that difficult to do it on all walls.

We are taking about insulating the floor from contact with the ground. So all permiters.

50mm is about optimum.
15 plaster + 18 skirting covers most of it.

Czhornet

sydthebeat wrote: »

errmmmm

theres 250mm of insulation between both leafs, to stop that happening.


Internal insulation has been shown over and over to be a sub standard method for a new build.

He didnt say he had any insulation, only a 250mm cavity. some people dont bother with cavity insulation if they are using the insulated slabs on the internal wall....

BarneyMc

Czhornet wrote: »

He didnt say he had any insulation, only a 250mm cavity. some people dont bother with cavity insulation if they are using the insulated slabs on the internal wall....

I WILL be pumping the cavity with beads. I can't imagine anyone would leave a 250mm cavity empty and try to make it up using insulated plasterboard on the walls. But then again you just never know! :rolleyes:

Czhornet

BarneyMc wrote: »

I WILL be pumping the cavity with beads. I can't imagine anyone would leave a 250mm cavity empty and try to make it up using insulated plasterboard on the walls. But then again you just never know! :rolleyes:

maybe not 250mm but I seen 100mm cavity left empty in a new build recently (2 yrs ago)
The other posters are right tho, the plaster, skim and skirting will cover the 25mm insulation up against the outer wall. I didnt bother doing it to the internal walls.

BarneyMc

On a similar subject is there a preference for which is done first, finished floors or plaster the walls?

delfagio

Hi guys, similar question for you on the perimeter.

I am little different in that I built with SIP panel house, I then installed 65mm insulated plasterboarding on all external walls internally. So this will act as my perimeter insulation also.

My floor insulation is 150mm so on my external walls I then used the edge insulation strip just to allow expansion of the floor screed.

However along door ways and two sets of double doors on the house where obviously there isn't insulated plasterboarding, I have run 50mm insulation along these door sections.

This will act as my thermal break here but it also leaves me with a section of about 150mm at the door way that will be filled in with screed/concrete. But when my final screed is poured on Tuesday next week. What will I do with the 50mm strip of insulation which will be cut flush with the floor. Can I just tile over this??

BryanF

Google foamglas or quinlite - you can detail out the thermal bridges.
The 50mm slab edge will have say a 20 skirting And 30 flooring over hang?

hexosan

Quinnlite's - €1.50/block approx

Foamglas - €21/block approx

I know which ones I'd be using.

BryanF

hexosan wrote: »

Quinnlite's - €1.50/block approx

Foamglas - €21/block approx

I know which ones I'd be using.

Under a threshold - foamglas would be my preference, because you can drive a nail into it with out it breaking.

sydthebeat

BryanF wrote: »

Under a threshold - foamglas would be my preference, because you can drive a nail into it with out it breaking.

Does it have enough compressive strength to take large triple glazed sliders?

BryanF

sydthebeat wrote: »

Does it have enough compressive strength to take large triple glazed sliders?

Yes

delfagio

Can floor finishes like tiles, laminate flooring be applied straight onto Foamglas??

hexosan

sydthebeat wrote: »

Does it have enough compressive strength to take large triple glazed sliders?

You can use it on the first course of the internal walls so no issue with compressive strength. You lay it on a bed of mortar with no joint just butted end to end. You can only lay one row as it clearly states they are not to be laid on top of each other.

I used it under my precast stair to limit the thermal bridge from the slab. Place in Blanchardstown sells them. I can route out the old email if anyone wants it.

BarneyMc

Strolling Bones wrote: »

We are taking about insulating the floor from contact with the ground. So all permiters.

So no real need to do on first floor (I will be installing UFH on first floor)?

PROJECT K

BryanF wrote: »

Under a threshold - foamglas would be my preference, because you can drive a nail into it with out it breaking.

pretty sure you are not supposed to fix anything into foamglass - I contacted them directly and they were quite adamant that the block must not be structurally compromised in any way. Screws/nails can fracture the glass structure and lead to failure. Also, while it has a significant compressive strength, you can push a nail through it with your hand so don't see any advantage trying to nail/fix anything to it...

PROJECT K

BryanF wrote: »

Yes

yes it does but see above post, you cant fix to it also risk of damage to foamlass during installation of slider...I had to remove a layer of foamglass because of this :eek: and replace with a layer of compacfoam (ultra HD EPS) instead...

PROJECT K

BarneyMc wrote: »

So no real need to do on first floor (I will be installing UFH on first floor)?

it is recommended to use perimeter insulation on all external and both sides of internal walls on ground floor, and all external walls on first floor (particularly if using UFH) - a reputable UF company will generally recommend this along with a suitable expansion strip

galwaytt

PROJECT K wrote: »

it is recommended to use perimeter insulation on all external and both sides of internal walls on ground floor, and all external walls on first floor (particularly if using UFH) - a reputable UF company will generally recommend this along with a suitable expansion strip

You should insulate under your heated screed to FF as well.

BarneyMc

galwaytt wrote: »

You should insulate under your heated screed to FF as well.

Yes indeed, it's just the perimeter insulation I wanted to check on.

BarneyMc

Hope to be putting in floors in about 5 weeks. What's an expansion strip. Also, has anyone gone ahead with 50mm PI? Having second thoughts now as I'm a bit afraid the tiles won't fix properly with so much insulation showing.

BarneyMc

BarneyMc wrote: »

Hope to be putting in floors in about 5 weeks. What's an expansion strip. Also, has anyone gone ahead with 50mm PI? Having second thoughts now as I'm a bit afraid the tiles won't fix properly with so much insulation showing.

Anyone?

sydthebeat

BarneyMc wrote: »

Anyone?

youd be looking at about 30 - 35mm between the plasterwork and skirting anyway.. so the remaining 15-20mm would be easily covered

tedimc

I'm thinking of using 50mm all around as well BarneyMc, but as one of the guys say, no-one will walk around the inner inch of the wall that would have any impact.

I don't think tiles not properly stuck down this close to the wall would be an issue. I'm not even using skirting, thinking of going with a shadow gap profile...

hexosan

Ive installed 50mm as well

BarneyMc

Do you lay the perimeter insulation first and then the floor insulation or vice versa? If it's the perimeter insulation then does it need to be nailed/glued to the wall to keep it there?

hexosan

Floor first in mine, then the perimeter insulation. I just stuck the odd bit of duct tape on it and the 1000 gauge plastic sheeting over all the insulation folded up the wall.

hexosan

I suppose you could push the odd nail down through it into the floor ins to hold it in place but not sure what cold bridge issues that might cause.

mjp

Will be doing self build next year but wondering who is best to talk to regarding what type of insulation to use and what is most effective. Are these outlined by BER assessor and do I have to abide by these to meet grading standard or will my blocklayer or guy who prepares foundation guide me on this.

Everyone seems to have differing opinions on whats the best option which is most confusing.

Gumbo

mjp wrote: »

Will be doing self build next year but wondering who is best to talk to regarding what type of insulation to use and what is most effective. Are these outlined by BER assessor and do I have to abide by these to meet grading standard or will my blocklayer or guy who prepares foundation guide me on this.

Everyone seems to have differing opinions on whats the best option which is most confusing.

Your Preliminary BER assessment will outline exactly what you have to put in in order to comply with Part L. Your blocklayer should have no input into your insulation choices imho.

You BER assessor will have to monitor the build in order to confirm that what he specified, actually goes in so that he can issue a final BER Certificate on completion.

I know you want to opt out of the AC role, but will you have some sort of professional guidance for the build?

rampantbunny

PROJECT K wrote: »

it is recommended to use perimeter insulation on all external and both sides of internal walls on ground floor, and all external walls on first floor (particularly if using UFH) - a reputable UF company will generally recommend this along with a suitable expansion strip

Is the insulation each side of the internal walls for:

1. Expansion
2. Reduction of heat loss from UFH heated screed to internal walls
3. Both

If 2, I'm not sure I understand the benefit if, your particular design ethos is to have block walls serving as thermal mass.

BarneyMc

rampantbunny wrote: »

Is the insulation each side of the internal walls for:

1. Expansion
2. Reduction of heat loss from UFH heated screed to internal walls
3. Both

If 2, I'm not sure I understand the benefit if, your particular design ethos is to have block walls serving as thermal mass.

I believe it's to reduce the loss of heat down into the subfloor/foundations.

rampantbunny

BarneyMc wrote: »

I believe it's to reduce the loss of heat down into the subfloor/foundations.

So I take it that even with thermal blocks used as first/second course, they would still leak heat thus rob the screed?

BarneyMc

rampantbunny wrote: »

So I take it that even with thermal blocks used as first/second course, they would still leak heat thus rob the screed?

I suppose to some extent but it's to do with reaction time also I believe.

BryanF

rampantbunny wrote: »

Is the insulation each side of the internal walls for:

1. Expansion
2. Reduction of heat loss from UFH heated screed to internal walls
3. Both

If 2, I'm not sure I understand the benefit if, your particular design ethos is to have block walls serving as thermal mass.

.

THE DON FANUCCI

hexosan wrote: »

I've 200mm eps in the floor and I'm using 50mm strips for the perimeter insulation.

how did you secure the perimeter insulation to the walls and damp proof membrane aswell ??

ker123

Anyone experience a problem with laying carpet grippers after installing 25mm perimeter insulation on both sides of internal walls??

And is it best to lay the floor insulation 1st and perimeter insulation 2nd or vice versa??

Bad_alibi

ker123 wrote: »

Anyone experience a problem with laying carpet grippers after installing 25mm perimeter insulation on both sides of internal walls??

And is it best to lay the floor insulation 1st and perimeter insulation 2nd or vice versa??

Floor then the perimeter insulation.

ker123

Bad_alibi wrote: »

Floor then the perimeter insulation.

Thanks