U value of “28mm Conservatory Panel”

Concerned_man

I have to replace the large wood framed side panel beside my front door, which has glass in the top half.

The bottom half (120 cm long x 100cm high) is plasterboard on the inside and plywood on the outside. The depth from outside to inside is about 7 cm… so not much space between inside and outside.


The Double Glazing companies want to replace the wood frame with a PVC U frame with glass in the top half, which seems OK

But they specify a “28 mm” PVC U “Conservatory Panel” in the bottom half. This seems very thin to me, but they assure me it will have similar energy efficiency rating as the glass but are unable to provide a u-value.

Does anyone know where I can find out what the u-value is… or have a better idea for replacing the bottom panel without reducing the hall space?

Thanks

robv_3

Anything above 28mm would be a special = expensive. Normally the u-value is improved by using low-e or high-e glass and filling between the two glass panels with gases like argon.

Normal is seen as 28mm plus low-e glass which will meet building regs.

Concerned_man

Thanks for your replies.

From your replies am I right in thinking that it makes little difference whether I put in the plastic panel or a double-glazed glass window in the bottom half of the door side panel.

I worry that the plastic panel seems to be so thin compared to the amount of insulation that we are expected to put in the loft.

Thanks

nrfoster

A 28mm double glazed unit, using the latest edge spacer technology (superspacer or warmedge), Superlow E + coated glass and argon filled cavity between 6.4lam and 4mm toughened glass will acheive a best case senario of 1.0 w/m2 K u-value (centre pane)

Polyurethane aluminium sandwich panel comprising of 1.5mm polyester powder coated aluminium each side of a 25mm polyurethane core to achieve a 28mm total thickness, will acheive 0.7 w/m2 K u-value..

So the alu-panel is 30% more effecient that the glass.:j