The free diy home improvement guide with answers to your questions on a wide range of do it yourself projects.

 

Boxing in the Steel Work

Previous Stage
Framing the New Roof

Next Stage
Slating the Roof

With the main roof of the new extension now covered, the work is moving on at great pace. Inside, the electricians have started the first fix for the new room, running lighting and power cables, and fixing mounting boxes for the sockets and switches.

New steel over the main opening New steel supporting chimney stack

In the meantime, the carpenter Mark has been boxing in the steel work in the old part of the new through room. You will remember that there is some fairly heavy gauge steel work that has been installed in this part of the building. One section spans front to back where the chimney breast was taken out and another section supports the back wall of the house where the ground floor room has been opened up to the new extension.

Timbers wedged between steel flanges Timbers supporting the horizontal plasterboard

Lengths of timber are cut and wedged between the flanges of the steel to provide a fixing for the vertical section. These are carefully measured so that they are a touch oversized. A bead of Gripfill is run along the back of the timber before they are lined up on the steel work and hammered into position so that they are good and tight. Timber battens to support the horizontal sections are then cut to length and fitted to the underside. On the main beam, these are continuations of the ceiling timbers for the new part of the room. Once these are in place on both steel beams, work can start on cutting and fixing the plasterboard.

As Mark explains, steel work like this needs to have appropriate fire protection. There are two ways this can be achieved – either by using fire resistant plasterboard which is easily recognisable by its pink surface or, by fitting two layers of 12.5 mm plasterboard. The latter is the method being used on this particular job.

Plasterboard fixed to battens on steel work Plasterboard fixed to battens on steel work

The height of the vertical section is measured and marked out on the plasterboard. This line is then cut with a knife before folding the board back on itself so that it snaps cleanly. The section is fixed in place with dry lining screws. In the old days, plasterboard was fixed with galvanised flat head nails. But drywall screws are far better. The drive in fast, have far more grip and, like galvanised nails, they won’t rust. The thing with that is that if the fixings rust, this will easily bleed through when it is skimmed with plaster and show up through the final decorations. The screws have sharp points and fit snugly on the driver bit. This means that they can quite easily be driven single handed.

Further vertical sections of plasterboard are cut and fixed in the same way before cutting and fixing the horizontal pieces. The horizontal pieces, as you can see, are fixed so that they overlap the verticals and are cut so that a ‘good edge’ of uncut board is left exposed.

Steel encased with plasterboard

In what seems like no time, the steel work is completely covered in for this end of the room and makes quite a difference to the overall look.

If you live in the Hertfordshire area and are looking for a professional building contractor, you can get in touch with G L Smith and Sons via their website: http://www.glsmithandsons.co.uk/

Previous Stage
Framing the New Roof

Next Stage
Slating the Roof

G L Smith and Sons