Question about kingspan

[Mike_scotland]

Hey group,

 

I have been upto my site and noticed some damaged insulation and some not fitted correctly (in my opinion) im pretty sure its a slight problem but wanted to know opinions before i speak to builder, please see attached photos and give me your opinion.

 

I can also say its being lined with vc foil then 30mm kingspan before sheeted in etc.

 

Thanks in advance. 

Edited November 27, 2021 by Mike_scotland

[Mike_scotland]

[Mike_scotland]

[JohnMo]

The insulation should be installed gap free, heat will just bypass the insulation, effectively taking the easy route.

 

Two options remove and replace with better fitting pieces.  Or foam fill the gaps to full depth, cut back flush once hardened.

 

What ever is done all joints should be taped with aluminium tape.  

 

Is insulation going above or below, to mitigate repeat bringing through the wood?

[Mike_scotland]

6 minutes ago, JohnMo said:

The insulation should be installed gap free, heat will just bypass the insulation, effectively taking the easy route.

 

Two options remove and replace with better fitting pieces.  Or foam fill the gaps to full depth, cut back flush once hardened.

 

What ever is done all joints should be taped with aluminium tape.  

 

Is insulation going above or below, to mitigate repeat bringing through the wood?

How do you mean above or below mate? 

 

Its meant to be 150mm insulation then, vc foil then 30mm kingspan over than?  

[nod]

That looks to be fitted quite neat 

Small gaps can be foam filled 

If you ask him to remove that You will upset him 

 

Edited November 27, 2021 by nod

[JohnMo]

I was meaning the 30mm you mentioned

[Mike_scotland]

Just now, JohnMo said:

I was meaning the 30mm you mentioned

I dont understand what you mean above or below? 

[Mike_scotland]

6 minutes ago, nod said:

That looks to be fitted quite neat 

Small gaps can be foam filled 

If you ask him to remove that You will upset him 

 

Just fill any gaps with foam?

[nod]

25 minutes ago, Mike_scotland said:

Just fill any gaps with foam?

Yes just foam up with a gun 

Cut off the excess the following day 

Some of our jobs (Housing associations) Require us to leave a 5 mil gap around the edges and foam up 

[Mike_scotland]

5 minutes ago, nod said:

Yes just foam up with a gun 

Cut off the excess the following day 

Some of our jobs (Housing associations) Require us to leave a 5 mil gap around the edges and foam up 

So it doesnt look too bad? I just assumed it was required to be as tight as could be... plus i think its getting vc foil next then 35mm more pir on top im hoping keeps us cosy!

[Mike_scotland]

[ETC]

Too many gaps. The boards should be tight fitting. It’s not difficult - show this to your BCO and get BC to tell him to fit them properly if you’d rather not tell him yourself.

 

Foam is only a sticking plaster and won’t have the same thermal resistance as Kingspan.

 

I presume you have a ventilated gap above the insulation and that you will be installing insulation or insulated plasterboard across the face of the rafters?

[Mike_scotland]

3 minutes ago, ETC said:

Too many gaps. The boards should be tight fitting. It’s not difficult - show this to your BCO and get BC to tell him to fit them properly if you’d rather not tell him yourself.

 

Foam is only a sticking plaster and won’t have the same thermal resistance as Kingspan.

 

I presume you have a ventilated gap above the insulation and that you will be installing insulation or insulated plasterboard across the face of the rafters?

Hi, thats what i was thinking, i will tell him myself he either fixes it or he doesnt get paid.

 

From what im led to believe there is slate on the outside then roofshield(i think its breathable) then i think a 50mm gap then 150mm kingspan and then vc foil thrn another 35mm kingspan. Does that sound about right?

[ETC]

Your rafters must be 200mm deep to allow a 50mm ventilation void behind the 150mm thick insulation along with 25mm over-fascia vents. The rest of the build-up including the thicknesses of all insulates should correspond with your SAP Calculation. Double check the location of the VCL - with Kingspan - I’m no expert but I would normally expect it to be below all insulation rather than between insulation boards but this can be checked with your designer and Kingspan.

 

Don’t be afraid to ask your BCO or any materials supplier for help with the correct technical advice.

 

You may even wish to send the photographs to Kingspan to see what they would say. If this was on any of the sites I visit I would tell them to do it properly.

[Mike_scotland]

6 hours ago, ETC said:

Your rafters must be 200mm deep to allow a 50mm ventilation void behind the 150mm thick insulation along with 25mm over-fascia vents. The rest of the build-up including the thicknesses of all insulates should correspond with your SAP Calculation. Double check the location of the VCL - with Kingspan - I’m no expert but I would normally expect it to be below all insulation rather than between insulation boards but this can be checked with your designer and Kingspan.

 

Don’t be afraid to ask your BCO or any materials supplier for help with the correct technical advice.

 

You may even wish to send the photographs to Kingspan to see what they would say. If this was on any of the sites I visit I would tell them to do it properly.

This is my SAP here, it has changed slightly but im assuming kingspan is slightly better 

[PeterW]

10 hours ago, ETC said:

Your rafters must be 200mm deep to allow a 50mm ventilation void behind the 150mm thick insulation along with 25mm over-fascia vents.

Not unless you have used breather membrane and then BCO may not require a ventilated void at all, or reduce to 25mm. 

[Mike_scotland]

3 minutes ago, PeterW said:

Not unless you have used breather membrane and then BCO may not require a ventilated void at all, or reduce to 25mm. 

I think thats what it is, we used roofshield quite expensive breathable membrane.

[ETC]

26 minutes ago, PeterW said:

Not unless you have used breather membrane and then BCO may not require a ventilated void at all, or reduce to 25mm. 

It’s not as simple as that. Check the caveats on the BBA Certificate. Not up to the BCO - they will take their steer from the BBA Certificate and BS.

[Onoff]

With gaps such as above and the practice of "foam filling" afterwards, isn't there a danger of the foam bridging the ventilation void across the full width, between the rafter? I mean, you can't see how much it's expanding the other side. 

 

Is it an issue?

[PeterW]

1 hour ago, ETC said:

It’s not as simple as that. Check the caveats on the BBA Certificate. Not up to the BCO - they will take their steer from the BBA Certificate and BS.

That is why I said “may not” as different membranes require different air gaps. Some BCOs require counterbattens even when the MIs do not require it, but ultimately it is the BCO signing it off so what is on the BBA certificate becomes sometimes irrelevant. 

[JOE187]

My thoughts are from your SAP  layer 5 and 6 should be swapped so  the ultra foil is on top of quinntherm and faces into the service cavity to produce best results.

[Mike_scotland]

9 minutes ago, JOE187 said:

My thoughts are from your SAP  layer 5 and 6 should be swapped so  the ultra foil is on top of quinntherm and faces into the service cavity to produce best results.

Hi Joe,

 

Its changed slightly now kingspan but there is 150mm kingspan then the foil then 30mm kingspan.... do you think the foil should be before the 150 KS? Would that not be a nightmare to fit as its in the rafters?

[Mike_scotland]

1 hour ago, PeterW said:

That is why I said “may not” as different membranes require different air gaps. Some BCOs require counterbattens even when the MIs do not require it, but ultimately it is the BCO signing it off so what is on the BBA certificate becomes sometimes irrelevant. 

I think the BCO here accepts alot of photos so does our seperate private building surveyor(warranty providor).... so if there is any problems do they have to get involved because after all they have signed it off as good?

 

After we are built and have the heating on i want a thermography camera survey to make sure not many leaks.  Maybe over kill but hey ho

[ETC]

2 hours ago, PeterW said:

That is why I said “may not” as different membranes require different air gaps. Some BCOs require counterbattens even when the MIs do not require it, but ultimately it is the BCO signing it off so what is on the BBA certificate becomes sometimes irrelevant. 

The BCO will not “sign” anything off and should not tell you how to design or build your roof - your BCO is an inspector, not a designer or a clerk of works.

 

The onus is on the applicant to comply with the Regulations and to ensure the construction complies with all relevant standards including the BBA Certificate for the material.

 

The BBA certificate needs to be complied with otherwise the manufacturer will not accept any liability for the materials use if used differently from its intended use. The BCO should never change construction methods detailed on a BBA Certificate.