24mm Double Glazed Sealed Units

24mm double glazed sealed units, made to your millimetres. Two 4mm panes with a 16mm spacer between them, 24mm overall, which is the standard makeup most UK window frames are rebated for. Made to the exact sizes you give us.

How to order

Pick the width band and the height band your panel falls into. We then make it to the exact millimetres you give us.

• 500 x 500mm is the smallest band. We will happily make a 400 x 400mm panel
• Largest size online is 2000 x 1100mm. Anything larger, or an unusual shape, is quoted individually - send us the sizes and we will price it
• Set the quantity to the number of panels you need at that size. Different sizes need adding separately
• Send us your exact sizes after you order and we will confirm them back to you before the glass is made

Plenty of window units are taller than 1100mm. We still make those, they just have to be quoted rather than bought online, so send us the sizes and we will come back to you.

What these units are for

• Replacing failed or misted units. The commonest job by a distance. If there is condensation between the panes that you cannot wipe off, the seal has gone
• Garden rooms, outbuildings and summer houses. New glazing into timber or aluminium frames
• Secondary glazing. Where an existing single glazed opening is being upgraded behind the original

A failed unit is replaced, not repaired

Worth saying plainly, because we are asked regularly. Once the perimeter seal on a sealed unit has failed, moist air is inside the cavity and it cannot be dried out, re-sealed or drilled and vented back to how it was. The unit is replaced. The frame, the beads and the hardware normally stay exactly as they are and only the glass unit comes out.

Measure the unit, not the frame opening

This is where most replacement orders go wrong, so please read it.

• Measure the existing unit, not the hole it sits in. The frame opening is bigger than the glass, because the unit sits back behind the beads on packers
• Give us the sight size and the overall unit size. Sight size is the glass you can actually see with the beads in place. Overall unit size is the full pane including the part hidden behind the beads. If you can take the bead off and measure the unit itself, do that
• Measure width first, then height, and take each one in two or three places. Old frames are rarely square
• Note which way round it goes on anything that is not a plain rectangle, and tell us before you order

A sealed unit cannot be trimmed down on site. It is made to the size you give us and it either fits or it does not, so check your figures twice before you send them. If you are not confident taking the measurements, talk to us before ordering rather than after.

Safety glass in a critical location

Standard units are made with annealed panes. Toughened panes can be specified where building regulations require safety glass, which normally means glazing low down in a wall, in or beside a door, or anywhere within the critical locations set out in Approved Document K. Ask when you order and we will build it with toughened panes to BS EN 12150 instead.

If you are replacing an existing unit, look at the corner of the old glass. A toughened pane usually carries a small etched stamp, and if the one coming out is stamped then the one going in should be too. If you are unsure, tell us where the opening is and we will say what we would normally supply.

Other options

Tell us before you order if you want anything other than the standard clear makeup. Obscure or frosted panes, a toughened makeup and different spacer colours can all be priced in. Holes, notches, cut-outs and shaped panels are priced individually, so tell us what you need before you order and we will price it. For anything shaped, stepped or out of the ordinary, use our bespoke service.

Delivery and handling

Most of our glass goes out on a pallet, and in the great majority of cases the vehicle has a tail lift and the driver has a pump truck. That is how it usually works rather than a service we can guarantee, so if you need a tail lift or kerbside help confirmed for your delivery, tell us before you order and we will check it. Have two people and a clean flat area ready to receive it and check it over before you sign. Sealed units are strong across the face and vulnerable on the edges and corners, which is where almost all breakages start.

Keep the units dry until they go in. A sealed unit stood in water is a unit you may be reordering. Glazing is a two person job on anything of size.

Related

• Single toughened panes cut to size: clear toughened glass panels
• Obscured glazing: 10mm frosted toughened
• Extra clear glass with no green cast: low iron toughened
• Laminated where the glass has to stay in place if it breaks: 10mm toughened laminated

A note on specification

The guidance on this page reflects what we typically supply for jobs of this kind, and is offered in good faith to help you order the right thing. It is not a structural specification and it is not a substitute for project-specific design. Barrier heights, spans, loadings, fixings, substrates and exposure all vary from site to site, and the final specification for your project remains the responsibility of you, your designer, your structural engineer or your building control body. We manufacture and supply to the sizes and specification you give us. If you are unsure, send us the details before ordering and we will tell you what we would normally supply for a job like yours.