Insulated slabs and heat pumps

Carrickbeg

A lot of new builds seem to not be putting in insulated slabs as the heat pump gives their build such a good EPC that they are not needed to meet the BER regulations?
What do you think of this?

mjp

Interested hear people's thoughts on this. Going with Daikin a2w unit with ufh and plan is insulated slab but it intersted hear what people make of this

BryanF

Carrickbeg wrote: »

A lot of new builds seem to not be putting in insulated slabs as the heat pump gives their build such a good EPC that they are not needed to meet the BER regulations?
What do you think of this?

Can you rephrase this? It doesn’t make any sense

dathi

Carrickbeg wrote: »

A lot of new builds seem to not be putting in insulated slabs as the heat pump gives their build such a good EPC that they are not needed to meet the BER regulations?
What do you think of this?

1. are you talking about insulated plasterboard slabs or concrete floor slabs
if you are talking about plasterboard most people are using a wider cavity and placing all the insulation in cavity if you are talking about floor slab it will need insulation.
2.you are mixing up BER with part L of the building regulations you must comply with all building regulations and the DEAP software is used to show compliance with part L of building regulations. the same software is used to generate a BER rating used when selling a home.

Dudda

I think by insulated slabs he means the insulated foundations system. eg https://www.kore-system.com/kore-products/floor-insulation/kore-passive-slab/what-is-kore-passive-slab and several other companies like Kingspan, etc also do them.

These give a better overall value to a new build by removing any cold bridges to the foundation which people use thermal blocks now to try and reduce. The idea is you have the UFH pipes in earlier in the foundation slab and you don't see a screed which helps on cost. I think they're a good system but aren't that common yet.

I'd recommend them in most cases except if you've a polished concrete floor. They aren't any saving as you really need to leave that towards the end so it doesn't get damaged. You'll still have to put a concrete floor on top of the insulated slab. In all other cases I'd recommend them and think they'll eventually catch on as energy regulations improve and passive house standards become more common.

Carrickbeg

BryanF wrote: »

Can you rephrase this? It doesn’t make any sense

Insulated plasterboards on the inside of all external walls...

sydthebeat

Carrickbeg wrote: »

Insulated plasterboards on the inside of all external walls...

a terrible construction method to begin with.

An_Toirpin

sydthebeat wrote: »

a terrible construction method to begin with.

It is so common! Even if made well so many new home owners don't realise that any new holes in their wall for picture frame etc can cause draughts.

BryanF

Carrickbeg wrote: »

A lot of new builds seem to not be putting in insulated slabs as the heat pump gives their build such a good EPC that they are not needed to meet the BER regulations?
What do you think of this?

BryanF wrote: »

Can you rephrase this? It doesn’t make any sense

Carrickbeg wrote: »

Insulated plasterboards on the inside of all external walls...

A heat pump, an EPC and insulated plasterboard slabs..

You design your house
You insulate your house
Then you design the heating system

I’m still not clear what your asking?

An_Toirpin

BryanF wrote: »

A heat pump, an EPC and insulated plasterboard slabs..

You design your house
You insulate your house
Then you design the heating system

I’m still not clear what your asking?

Well in private estates it seems what is considered good practise is not being met?

Carrickbeg

BryanF wrote: »

A heat pump, an EPC and insulated plasterboard slabs..

You design your house
You insulate your house
Then you design the heating system

I’m still not clear what your asking?

Ok I'll give it another go...under current regulations for BER if you use a heat pump you can have 100mm cavity wall insulation but if you use a gas/oil furnace you have to use 200mm insulation (150mm cavity insulation and 50mm internal insulation) in order to achieve a sub 4.0 EPC...

sydthebeat

Carrickbeg wrote: »

Ok I'll give it another go...under current regulations for BER if you use a heat pump you can have 100mm cavity wall insulation but if you use a gas/oil furnace you have to use 200mm insulation (150mm cavity insulation and 50mm internal insulation) in order to achieve a sub 4.0 EPC...

No.

Things are no where as near as prescribed as that.

froshtyv

Carrickbeg wrote: »

Ok I'll give it another go...under current regulations for BER if you use a heat pump you can have 100mm cavity wall insulation but if you use a gas/oil furnace you have to use 200mm insulation (150mm cavity insulation and 50mm internal insulation) in order to achieve a sub 4.0 EPC...

In the current building regs you have to achieve 0.21W/m2K or better for external walls.
This can be done several ways and has nothing to do with your heat source.

The EPC figure in the BER is made up of several factors calculated be DEAP.

A heat pump generally helps lower the EPC figure because of its make up.

sydthebeat

froshtyv wrote: »

This can be done several ways and has nothing to do with your heat source.

Everything in DEAP affects everything else, so you can't say it has nothing to do with your heat source.
Certain sources will require a better elemental u value....