Bifold doors

12 Feb 2009
Reaction score
United Kingdom
At present I have a set of 2400 x 2350 aluminium sliding doors which are to be replaced with a set of timber 2400 x 2090 bifold doors.

Due to the height difference I can not fix to the existing beam above so I was intending to bridge the gap needed by fixing a 2400mm timber to the bulkhead above (hopefully steel beam) and construct a new wooden beam to act as a new bulkhead for the new doors from 2 x 75 x 35 c 16 pressure treated timbers, bolted together to make 1 x 70 x 150 beam fixed via joist hangers to 2 plates of wood 300 x 600 x 35 fixed via 4 x 110mm masonary screws (to each plate). The left over space between the new bulk head and new beam I intended to add supports every 600mm running vertical, fixed via ties.

My concerns are whether the above would be adequate to support the doors when fully open. The bifold doors would be fixed accordingly to the blockwork side walls and floor, however will the new bulk head be suffice? The joist hangers support 1.1kn short uplift 3.2 km long term (each I presume) while the doors weigh 101kilos. If my calcs are correct the load should be fine however when the doors are fully open will the load hang down or pull out??? The doors are top hung will a timber joist be strong enough for the job? In theory I am fixing a 220mm timber to the side walls and bulkhead (steel or catnic beam).
Sponsored Links
A quick google around showed a couple of companies offering bifold in upvc at 2400 height for similar money, I'm sure you could get them foiled to colour match, and they don't need maintaining.. See what your options are for getting doors to fit, rather than cutting down your light and headroom?
Sponsored Links
^^ Eeeew. Plastic bi-folds are the pits

That's a good price for those doors from screwfix. It's a pity the 3m ones are not such a good bargain. :(

Anyway, I don't think an infill beam will be an issue as this will be fixed to the existing lintel/beam above and if that is OK, then it should all work.

Also think about fixing this infill beam to the jambs (angle brackets?) to make it more secure, stop it rotating and to transfer some load to the jambs

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local