Multi-Width Insulated Cavity Closer (pk 10)

The multi-width insulated cavity closer is one of those products that quietly earns its keep on site. It bridges the gap at window and door reveals, closing off the cavity to prevent cold bridging, damp ingress, and the kind of draught that makes an otherwise solid building feel like a barn in January. Available in two size ranges — 50-100mm and 100-150mm — so you can match it to the actual cavity width rather than bodging something close enough and hoping for the best.

The PVC flanges and insulated core are designed to sit cleanly in the reveal, and because the product accommodates a range of widths within each size variant, you are not hunting around for an exact match every time a spec changes mid-build. That flexibility matters on real sites where cavity widths are not always what the drawings say.

Installing the Easi-Close Multi-Width Cavity Closer

One of the more useful things about this closer is the number of ways it can go in. You can tack it directly to the window frame if the frame is being built in. Alternatively, it friction fits into the reveal as the brickwork goes up, which suits most new build situations where you are working course by course. If the reveal is already constructed, it can be fixed to the inner leaf using grab adhesive — handy for remedial work or where the sequence has got away from you on a busy site.

Jointing and Corner Details

Where lengths need to be jointed to reduce waste, sections can be butted together at 45 degrees, angled downward toward the outer leaf. This is not optional — it is the correct method, and it stops water finding a path through the joint. At corners, trim both PVC flanges and let the vertical piece run down past the horizontal. Again, this is about keeping water moving in the right direction rather than sitting in a joint waiting for somewhere to go.

Sold in packs of 10, the multi-width insulated cavity closer suits bricklayers, window installers, and groundworkers on new build plots, extensions, and renovation projects where the reveal detail needs to be done properly first time.