Hybris insulation v Celotex?

[CarrieBuild]

Purchasing a garden room!

 

....my preferred quote provider uses Hybris insulation in the walls...I note a discussion on this forum a few years ago saying Hybris wasn't very good...have things changed? 

I want a really well insulated room.

 

Thanks

[SteamyTea]

44 minutes ago, CarrieBuild said:

have things changed

Laws of Physics are the same.

 

[JohnMo]

Biggest trouble is no-one installs it per the manufacturer instructions, with air spaces either side of the insulation.  By the time you have the correct airspaces it's no better than much cheaper glass wool on a depth by depth basis.

[Temp]

6 hours ago, CarrieBuild said:

Purchasing a garden room!

 

....my preferred quote provider uses Hybris insulation in the walls...I note a discussion on this forum a few years ago saying Hybris wasn't very good...have things changed? 

I want a really well insulated room.

 

Thanks

 

Hybris has changed over the years. Data sheet currently says the Thermal Conductivity is 0.033 W/m.k The equivalent for PIR/PUR insulation is 0.021 to 0.028 W/m.k. Rockwool is about the same as Hybris 0.035 W/m.k. Lower numbers are better. These number are for a unit thickness (1m thick!) so you can (only) compare them if the thickness of each is the same.

 

Before you buy your garden room ask what thickness of insulation they provide or what the U-Value of the wall and ceiling will be. Hybris is available from 50mm to 205mm thick. So anywhere from poor to pretty good depending on how thick they use.

 

If you insulate it yourself I'd look at Rockwool between studwork and possibly a layer of PIR/PUR or insulated plaster board on the inside. Rigid insulation like PIR/PUR is hard to cut accurately to fit between studwork where as Rockwool can be cut oversize and squashed in.

[JohnMo]

But as I said above it has to be installed with unventilated air gaps either side of the insulation, as to get the thermal conductivity advertised it relies on low emissivity of the reflective coating.

[CarrieBuild]

Should I just specify celotex instead?

[Ferdinand]

On 01/06/2022 at 14:01, CarrieBuild said:

Purchasing a garden room!

 

....my preferred quote provider uses Hybris insulation in the walls...I note a discussion on this forum a few years ago saying Hybris wasn't very good...have things changed? 

I want a really well insulated room.

 

Thanks

 

I'd suggest your point of comparison could perhaps be Building Regulations requirements for the walls of a new house, or an extension to an old house.

 

I did a sun lounge from a repurposed conservatory a few years ago, and installed 100mm of rockwool in the roof, 75mm of celotex in the floor, and 50mm of celotex in the walls. The tenant has been very happy, and that has become the main living-room throughout the year.

 

The thing you do need to provision for is overheat in summer. My T has her dog-crates in the sun lounge, so uses an air-con to manage the temperature for a week or three in the summer. Make sure that decent ventilation is available.

 

In a garden room I would perhaps suggest a reversible A2A heat pump as a good option for warmth and coolth.

[Iceverge]

Mineral wool/Rockwool every time. Cheaper, better fit, fire performance. Overheating protection. The list is long. 

 

Once you have any insulation at all ventilation losses become a far more significant factor, especially in small buildings.  What airtightness/draft proofing strategy have you agreed on?