Frequently Asked Questions

Q What are the U values?
There are no u values on cavity closers the calculation required to meet part L building regulations is the path of thermal resistance, closers have to meet a minimum of 0.45m2KW (all Subframes closers meet this criteria).

Q Do the cavity closers have the required European CE mark?
CE marks do not apply to cavity closers, unlike windows & Glass

Q Are all cavity closers fully insulated?
No depending on the design of the cavities within the closer some such as Duraflex do not require full insulation as long as they meet the 0.45m2KW path of thermal resistance they comply to Part L (and they do).

Q Which is the inside and the outside of the closer?
It does not matter with a fully insulated closer unless one lip is longer than the other in that case the longer side goes to the inside face, if only partially filled the insulated side goes to the outside face.

Q How quickly can they be delivered?
Within 7 to 10 Working days, in reality any closers ordered this week will be delivered next week

Q What cavity sizes can we supply?
From 50mm to 300mm

Q Are standard cavity closers fire rated?
No only Thermabate which has 30 minutes

Q Do you supply 1 hour fire rated closers?

Q Do you supply closers for steel and timber frame builds (including Metsec)?

Q What do you do if it’s a split lintel design?
4 sided closer required

Q Can widows be fixed direct into closer?
No not with standard closers but we can supply closers to fit this requirement on request

For quotations, product information or technical support please call us on 01773 590100, fax 01773 590200 or email

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