Approved Document M of Building Regulations requires certain accessibility features are made for mobility access to new builds and/or new extensions, porches etc for the main entrance to a dwelling.

When manufacturing a door frame we are able to supply different options of Mobility Access Cill (or sometimes spelt as Mobility Access Sill). Any of our door frames can be made to comply with Document M by following the guidelines below. Also ensure that a 33" wide door or larger is used for single dwellings (narrower are not compliant with Doc. M Mobility Access).

We would recommend the SLT Slimline cill in most applications and indeed include this with our purpose made frames and pre-hung door sets but in areas of heavy wheelchair traffic we would recommend using the TRX mobility access cill.

Below are examples which follow guidance in the publication ‘Accessible Thresholds in new Housing’ published by The Stationary Office.

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Typical Standard Door Frame Detail with Waterbar

Note: Does not meet Document M

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Typical Door Frame Detail with SLT Slimline Mobility Cill

Note: Designed to meet Document M

This is the mobility cill we use on our pre-hung external door sets when using a standard hardwood external frame pack

Suitable for standard hardwood frame packs

Click to view SLT Slimline Mobility Cill

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Typical Door Frame Detail with TRX Mobility Cill

Note: Designed to meet Document M

Not suitable for standard hardwood frame packs

Click to view TRX Mobility Cill