Strengthening Roof Joists For Loft Conversion

Trussed rafters loft conversion.

Strengthening roof joists for loft conversion.

This is part 2 in my series of loft conversion videos. Sistering is the process of adding a new joist next to each existing joist. Loft conversion animation by wasim duration. A 175mm loft leg fixed on top of a 100mm truss or ceiling joist provides a lightweight cost effective solution.

I have consulted a structural engineer and he has advised me that the loft joists are not strong enough to handle it and will need strengthening. Shafix design install 1 504 034 views. Although once regarded as hard to convert on account of their relatively slender roof timbers typically only about 30 x 70mm many lofts of this type have been successfully. It is at this stage when the dormer windows are being constructed that your loft conversion will be exposed to the elements so you ll need good temporary sheeting to protect against the weather.

You can do this by adding larger and stronger timber floor joists between the existing ceiling joists. Developed by a team of engineers and designers the loft leg is strong. Most roofs built from the late 1960s onwards are of prefabricated trussed rafter construction with distinctive w shaped webbing. The plan is just to put down some 18mm chipboard insulate the roof and board off the roof and eaves.

In the case of 2x6 joists you can pair them up with additional 2x6 joists by nailing them together side by side. In this video i show how i cut my my joists make packer plates get the joists from the garden up int. A ridge beam is installed beneath the apex before the dormer roof joists can themselves be fixed in place and the roof weathered.