ROOFERS AT IT

The roofers started their work last week Thursday afternoon. As of this morning, they were about halfway, and are apparently under instruction from their boss to finish up today, whatever it takes. The roofers erect 76x50mm structural grade pine purlins over the rafters, with bracing where required by the engineer. They then attach Alububble insulation to the purlins with double sided tape. And the roof sheets are then screw fixed over this into the purlins.

The Alububble is a composite roll of bubble-wrap type white plastic insulating membrane with a foil lining on the upper side. This acts both as a water barrier in case of roof leakage, as well as an primary insulating membrane. We will supplement this insulation with further insulation above the ceiling boards.

The roof sheeting is formed from BlueScope Steel Colorbond Ultra steel in flat sheet roll form. It is then cut and pressed locally into IBR [inverted box rib] profile. The steel rolls come pre-coloured. We picked the White colour, for superior heat reflectivity. The steel is 0.53mm thick, and coated in a galvanising aluminium/zinc alloy with a coating mass of 200g/sq.m. The coloured paint is then bonded to the sheeting. The steel is imported in roll all the way from Australia, which is a pity. However, we were not prepared to purchase the locally produced Chromadek coloured galvanised steel sheeting produced by Mittal Steel, as it is widely held in the industry to be a vastly inferior product to the Colorbond. Environmentally, life cycle costs are just as important as initial build costs, so its a balancing act and a judgement call one has to make.

Roofing goes on while Table Mountain looks on

Interior view with Alububble underside visible

WAITING FOR THE ROOF

The roof rafters are up, and we have appointed A&A National roofing contractors to fit the roof sheets. So far, I am not impressed. They were due to start on Monday 20 February 2012, then it became Tuesday, then Wednesday [today]. I was contacted by them this morning to say they may only be on site after midday today, and perhaps only tomorrow [Thursday]. If I had known this ahead of time, I would have had the builder on site this week to finish up a few odds and ends.

The builder spent last week building in the timber roof rafters, and started screeding the floors. If it wasn't for the roofers messing with our scheduling, the builder could have finished the floor screeding this week.

In the meantime, we have appointed EcoBeam to supply our floor joists. Not only can they supply them in next to no time, they have significantly undercut their competition in quoted price. The joistS should be on site next week, and we are looking forward to getting the first floor structure up. Fingers crossed that the roofers finish up by Friday...... 

Rafters wating to be roofed

Rafter ends clipped due to flush eaves

First room has its screed

THE END.....OF THE BRICKWORK

The brickwork is finally done! The final profile shape of the house is now clear, and is pretty much as expected. It does not overpower the surroundings, but it certainly has presence. All that remains is for the builder to build the roof rafters into the brick walls either side.

Internal cross wall to finished height

Finished height of the gable overlooking park at rear of site

View from West corner

The roof timbers were delivered to site today. They were supplied by Okavango Trusses, who also provided the necessary structural design for the roof. The main part of the roof structure is the 228x76mm rafters, in SABS Grade 5 treated structural pine. Each of the 20 rafters is 6.3m long. Their ends will be wrapped in damp proof plastic sheeting, and built into the tops of the brick walls. Although the pine will be hidden behind ceiling boards, it has a beautiful grain and is quite knot free. A very underrated timber.

Pine is much maligned in South Africa, due to its thirsty habits [this is a dry country after all]. Although it may be true that pine plantations do rob river courses of much rainfall run off, I think people tend to ignore the real point of building with wood. Not only is it carbon neutral and completely renewable. I am certain that a home built of plantation pine uses far less water in the production of its structure than an equivalent concrete or brick home, due to the energy and mining intensive nature of cement and brick production.

The roof timbers lie in wait

Nice grain

This past weekend we also dug a trench from the house to the electricity distribution box on the street. In it we buried 20m of SWA [steel wire armoured] cable, to enable Eskom [the local electric utility] to hook us up to the grid with a temporary connection for building work.

Electric cable follows side of house....

...then runs diagonally towards the street...

...and under the boundary wall foundation to the electricity box.

So this week the roof structure should be up, and then all that remains of the builder's contract is the screeding of the ground floor slab, and chasing three ducts on the outside of the brick walls for bathroom soil pipes. Hope he gets it all done by Friday!

IT'S GETTING LOFTY

Just a brief update on the progress. The work currently underway is more of the same, bricklaying, bricklaying, and more bricklaying. 42,000 bricks in total. So not much to report, other than that the brickwork is getting higher, and work is on schedule.... See for yourself.

East corner view

South corner view

West corner view

North corner view

30mm insulation in the wall cavity

A view from the Garage through the Kitchen to the Living Room: 24m!

One day I'll grow up and be the Living Room