Designing and constructing a traditional half span hipped end roof  Roof to a domestic extension

The Contract This is a learning module demonstrating the procedures and techniques used to plan, design and construct a traditional half span hipped end roof for a domestic extension.

The initial procedure The first step was to study the drawings

Secondly, I produced a geometrical drawing to work out the materials required from the true lengths and quantities.

The third step was the fitting and fixing of the wallplates onto the blockwork. The wallplate bedded onto the blockwork with mortar and secured with restraint straps I was now ready to start the construction of the roof structure

Rafters across wallplates To work out the true lengths and bevels on site we lay rafters across the wallplates and use them as a full size roofing square as shown in the following slides Working out rafter true lengths and bevel cuts

Work out the common rafter lengths and bevels Half span Rise Wallplate to the extension Existing house wall

Work out the hip rafter lengths and bevels Hip on plan Rise

Once we have worked out the true lengths and bevels we need to mark out the rafters as shown in the next two slides

True length common rafter Plumb cut common rafter 2/3 depth Pitch line The birdsmouth cut is achieved by marking a line at 90 degrees to the plumb cut line Setting out a common rafter Rafter Timber

True length Hip rafter Plumb cut Hip rafter 2/3 depth of common Pitch line The birdsmouth cut is achieved by marking a line at 90 degrees to the plumb cut line Setting out a Hip rafter The true length is now measured from this centre cross line

Making “A” frames Once you have marked out four common rafters you are now in a position to construct two “A” frames as shown below: Common rafters Note position the top brace to sit the ridge on Temporary braces nailed to form the frame. Ridge

Positioning the “A” frames on the wallplate : Plan view Ridge “A” frames Half span Wall plate Common rafters

The common rafters in position The first pair of common rafters are in the “half span” position

Common rafters fixed with truss clips to the wallplate

RESTRAINT STRAPS

Common rafters with saddle board

Positioning and fixing the Hip rafters : Plan view Ridge “A” frames Half span Wall plate Common rafters Hip rafters

Hip rafters fixed to the saddle board

Hips

Hip rafter with “dragon tie” to the wallplates

Positioning and fixing the Jack rafters : Plan view Ridge “A” frames Half span Wall plate Common rafters Crown rafter

Jack rafters meeting the Hip

Ridge, common, Hip and Jack rafters

Commons Hips and Jack rafters

Front view ready for fitting the fascia

Positioning and fixing the fascia board : Plan view

Fitting the fascia and timber as carriage brackets

Fitting the fascia with a mitred corner

Eaves details Horizontal timber off cuts used as carriage brackets for the fascia and soffit board

Carriage brackets

The completed roof structure