Standard expected

[MikeFleming]

Hi,

I am having some work done, and am getting charged for variations when I am not sure I should be.

An example is insulation. Kingspan Koolthem was specified, and there is some aspects of this installation that are not being done as per the manufactures recommendations in the datasheet for the product.

These things have not been detailed on the specification, but not everything surely needs to be. Is there not an expectation that things shpuld be carried out to a reasonable standard, and what should that standard be? If the product manufacturer says it must be done in a certain way, should that be expected to be implied?

Thanks

 

[Doggit]

Sorry Mike, but you're being too hypothetical. Sometimes the builder will deviate from the data sheet, because of his experience and ability to the job in a more reasonable manner, and sometimes data sheets don't always relate to real life, just standard scenarios.

 

[John D v2.0]

In theory it should all be done according to the book, but things vary a lot, the builder will quote for something pretty similar to the drawings, what he usually does, maybe some builders will do things to the letter and others will just make things look just about right from outside.
We had an architect on side to inspect and determine whether any of the many deviations were ok, bad practice but should be ok, or not ok at all. That let us focus on bad areas. Still had a fair bit to redo ourselves, but unless you're lucky you never know how the builder will do it on the end.

What are the deviations out of of interest?

 

[Notch7]

Kingspan Kooltherm is PIR foil coated insulation. Whatever the brand they are all virtually the same product.

Provide some specific examples of non compliance with method specified.

What variations?

 

[MikeFleming]

Thanks Doggit, Ill give one problem as an example.

In the attic, I have 90 mm collar joists, with 100 mm between joist insulation. The datasheet says that if the roof space is usable (I have also asked for a loft hatch, so there was not doubt it was intended to be usable) the insulation should not be above the top of the joists (otherwise any load on the insulation would push it down into the ceiling - its the joists that should bear the weight only). It calls for battens to be placed on top of the joists.

Given this is a requirement from the manufacturer, and given it would make to the roof not fit for purpose (and the installation of a loft hatch pointless), do you think this is an extra?

Thanks

The insulation must not be used as a weight bearing surface and, if the thickness of insulation exceeds the depth of the joists, batten out the joists such that they stand proud of the insulation

 

[MikeFleming]

Thanks others as well. Didn't see your messages before posting, I think I answered in that message.

 

[endecotp]

Kingspan Kooltherm is PIR foil coated insulation. Whatever the brand they are all virtually the same product.

No it isn't; it's phenolic, not PIR. There are various brands of PIR that are all much the same, but Kooltherm isn't one of them.

 

[Doggit]

Now if you've got 90mm joists, how have they fitted 100mm insulation. Yes, they should have battened the joists to raise it to the level of where the insulation would fit. If they haven't done that, then it's definitely shoddy workmanship. Stand your ground, and get them to do it properly. I'd be inclined to add a 1.5" batten to make sure that it's always above the insulation level.

 

[John D v2.0]

In the attic, I have 90 mm collar joists, with 100 mm between joist insulation. The datasheet says that if the roof space is usable (I have also asked for a loft hatch, so there was not doubt it was intended to be usable) the insulation should not be above the top of the joists (otherwise any load on the insulation would push it down into the ceiling - its the joists that should bear the weight only). It calls for battens to be placed on top of the joists.

I think you're pushing it a bit!
It's been installed to the manufacturer spec, the builder won't price for thing you don't ask for. This is where a proper spec helps you.
If you ask for a loft hatch the builder will quote for a loft hatch. He won't quote for battening, boarding, light fittings and switches, a loft ladder, shelving, etc, otherwise where does he stop?
Building work is an absolute mine field of confusion in this way unfortunately.

 

[John D v2.0]

looking at the replies, you can see it's a grey areasorry for the confusion!

 

[MikeFleming]

No it isn't; it's phenolic, not PIR. There are various brands of PIR that are all much the same, but Kooltherm isn't one of them.

That was another thing. He got the cheap stuff. I told him to put in what was specified. He wasn't happy. I did offer him to give me 2k and I would accept the other stuff as I felt bad about him losing the money on the other stuff and having to wait for the Kooltherm but I think he thought I was just trying to get money off him. He didn't see there was any difference between the products.

 

[MikeFleming]

Yes, thanks. TBH, the architect is calling it a variation, but I wasn't sure I agreed. I wonder is there any case law on this?

 

[Doggit]

Kingspan and cellotex have gone up in price because of a fire in one of the chemical factories. Give Kingspan tech support tomorrow, and get their opinion.

I think you're pushing it a bit!

I'm not sure he is to be honest John. As he's specified a loft hatch to be installed, then he's obviously intending to go in the loft, but as the insulation is going to be sitting above the joists, then it'll either get crushed as he tries to walk round the loft, or he risk pushing it downwards and breaking the ceiling below it. Yes, I'd say that he hasn't adhered to the standards of how it should be fitted, and he should have quoted for the job to be done properly, not half heartedly.

 

[John D v2.0]

As he's specified a loft hatch to be installed, then he's obviously intending to go in the loft,

I see what you're saying and the builder could have queried it, but in pricing a job they aren't going to spend hours asking questions, the builder just wants to price what's asked as pricing takes long enough as it is. AA i say, how does he know where to stop, and how does he know what people will do DIY or separately. He has to assume one way or another. Putting the assumptions on the quote in writing would have ensured the difference was picked up, but it wasn't unfortunately.
If the op said the builder was boarding directly on top of the insulation, I'd be right there with you, completely unacceptable, but as it is my personal opinion is the builder hasn't done anything wrong, just different.
I can see your point entirely and I understand fully so we will have to agree to disagree

 

[Notch7]

No it isn't; it's phenolic, not PIR. There are various brands of PIR that are all much the same, but Kooltherm isn't one of them.

Oops! My error... apologies.

I see phenolic is more expensive and about 10% more efficient.