It’s time for a roof

The beginnings of a metal roof

We’ve managed to finish the majority of the ply roof sub-base, and the roofers from Cornwall Zinc Roofing have started with their part.

A specialised membrane is installed on top of the plywood, and the final metal finish will sit on top of this membrane.

The fascias and first strip of metal have been installed and can be seen at the bottom of the photo.

This is when the building starts looking like a house, and it’s part of what will make it watertight and therefore open up loads of other work that we can’t really do while water is streaming through!

Now the real work starts

Preparations underway for the metal roof

Our timber frame completed a few days ago, and since then, we’ve been planning and getting materials ready for installing the first few layers of the roof. This will make it ready for the metal roofing company to arrive and install the final finish.

There are essentially four things that need to be done at this stage.

Breather membrane

First is to install a breather membrane, which can be seen in blue in the photo above. This is similar to the familiar roofing felt which is installed under tile or slate roofs. While in that case it provides waterproofing, the breather membrane here simply provides a means of covering the roof and allowing any condensation to bead off.

The membrane comes in long rolls that we pre-cut so that each length was half of the overall length of the roof. This allowed us to install it more easily on site, which we did by stapling it to each roof truss using a heavy duty staple gun.

It’s important to layer each row of membrane on top of the row under it so that any water drips onto the next row on its way down rather than dripping underneath and into the loft space.

Battens

Next are the battens. These are long lengths of wood, 50mm × 50mm square and 4.7m long, that are attached parallel to the roof trusses running from top to bottom. This is as opposed to battens used for tiles or slates that run perpendicular to the roof trusses, from one end of the house to the other.

These battens do two jobs – they completely pin down the breather membrane and they provide a gap of 50mm between the membrane and the next layer. This gap allows air to pass and ensure any water or condensation is cleared away.

We installed these with 90mm corrosion-resistant wood screws. We chose screws that are self-drilling so that we didn’t need to pre-drill any pilot holes, and ones with Torx (star-shaped) heads to help them slip less when using a drill. 90mm ensures they go through the 50mm batten and 40mm into the roof truss for a secure attachment.

Plywood

Thirdly, we have the plywood. These come in large 2.4m × 1.2m sheets that are 18mm thick and weigh about 36kg each! The plywood provides a flat deck on which the final metal roof will be installed. Since we’re using the plywood for roofing, we went with WPD structural plywood. This is a waterproof plywood that is designed for structural loading.

The detail from the roofing company specified that the first 150mm at the bottom of the roof should be 12mm plywood instead of 18mm, so we cut these strips and installed them first. Then we cut the main ply sheets so that they always start and end on a batten (this is important to make sure they’re fully supported). It’s also important to make sure each row is staggered so all the joins don’t line up – this ensures maximum structural integrity.

We installed these with a first fix nail gun. This is an invaluable tool that we hired from Jewson along with a set of 90mm nails. This made the installation much faster.

Fasicas and barge boards

Finally, we need to install the fascias and barge boards. These are narrow strips of 18mm plywood that run across the front and back of the roof as well as up and down the gable ends at each side. Guttering is attached to these boards. These will also be nailed using the nail gun.

Once all of these jobs are complete, the metal roofing company will install the aluminium standing seam roof and one job will be complete!

We have a roof

Workers installing the roof trusses

We’re now nearing the end of our timber frame initial build and the roof trusses are being installed. The real shape of the house is turning into reality!

Once these are all in place, the only remaining task will be to install the gable end panels, after which the timber frame will be complete and we’ll be able to start on site.

Our first task is to make the roof watertight ready for the metal roofing to be installed. This is booked to start in around a week and a half, so we have a very hard deadline to work to!

First floor going up

First floor being assembled

A few more days in and the walls of the first floor are being assembled.

Entire wall panels are delivered on trucks and then lifted into position using a crane, where they are then attached to the floor and ceiling. All the external panels are pre-insulated and battened ready for plasterboarding once the house is watertight.

At the bottom of the photo the top of the roof trusses can also be seen. These have been delivered early but will soon be lifted into place to form the roof and loft space.

One floor down

Completed ground floor frame

It’s amazing just how quickly a timber frame gets put up once it starts!

After the soleplates and damp proof membrane were installed yesterday, it’s only taken a day to complete the frame on the ground floor.

Next up, the beams and joists will be going in, ready for the first floor to be completed, and within a couple of week we’ll have a complete timber frame ready for roofing.

We’re lucky to be able to use our next-door plot to site the telehandler that’s lifting the panels into place, and a few ground protection mats make sure it moving around doesn’t damage the levelled ground.

Bring on the timber frame

Block and beam ground floor complete

The last couple of weeks have seen a flurry of work on site as the groundworks are concluded. Since the last post, the block and beam floor has been laid and grouted providing a solid surface. The outline of the ground floor has also been laid with a layer of blocks on which our timber frame will sit.

Groundworks are now complete and we have a small week-long lull while we organise site visits and bring the next few trades into the schedule.

Next week, the scaffolding will go up around the perimeter, and the week after that, our timber frame build starts in earnest! As soon as that’s up, the metal roof installation will start, and this is also when we’ll get our hands dirty to do some of our own work, like insulating the loft space.

Finally, last weekend we installed our second, time-lapse camera on site. We’ve set it up but have no way of checking the result until we take it down, which we’ll do once the external block work is complete and there’s not much else to see outside.

The blocks are in

Outside edge foundation blocks laid

A couple of weeks since we last posted and things have been moving along nicely.

In that time, all the trenches were dug so that inspections for building regulations and mining could be completed. Once those were done, the concrete went in along with some reinforcing mesh.

We’ve now started on the blockwork on which the timber frame will stand. The outside edge of our foundations are now pretty much complete and some of the internal walls have started too. We’re hoping that the blockwork will be completed in the next few days, allowing the beams of the block and beam floor to be laid.

In other news, the timber frame design is now locked down and the structural steel elements have been sent off for manufacturing and the frame is scheduled to be bought on site in a few weeks’ time.

Finally, we had little luck coercing the existing camera (source of the photo above) to take regular photos for a time-lapse video at the end and so we’ve found another specialist build camera that has built-in support for time-lapse videos and runs on batteries. It doesn’t have any internet connection, however, so we’ll set it up before the frame starts being built and will probably move it inside at some point to capture the internal work. We’ll keep using the existing camera to be able to keep an eye on work from afar and take still photos on-demand.

Foundations away

The foundations have started!

A couple of months since our last post, and a lot has happened in the world, although not on our plot! As expected, COVID-19 bought everything to a pause as we tried to work out our next steps.

Happily, construction workers got the go-ahead on Wednesday and after discussing with our groundworker, we agreed to start with the trench dig.

The pause gave us time to catch-up on paperwork, including the final construction designs from Frame UK, building regulations approval and structural calculations.

More updates will come shortly as we progress with the foundations.

Retaining walls, cameras and building regulations

Most of the retaining wall (and me digging a hole!)

It’s been a bit more than a month since we last posted, and a lot of that time has been taken up by architectural stuff – tweaking door placements, finishing off all the drawings and bringing together the work done by our structural engineer with the SAP (energy efficiency) calculations ready to submit to building control.

In the meantime, our groundworker has been doing his part to keep the build going by taking our ground levels down to the final finished floor levels on our plans. The level of the mud in the photo is pretty much the level the ground floor of the house will be at.

In our back garden, we’ve opted for split-levels, mostly to save on extra soil digging but also to provide some more interest. However, this does mean having a retaining wall to stop the back part of the garden collapsing. The photo shows most of the wall up (and since then, the rest has been finished off). We haven’t decided yet what the finish on the wall will be.

This is pretty much the limit of work that can be done before our architectural drawings are passed by building control and our timber frame provider has calculated what they need in terms of foundations (validating and tweaking the work done by our structural engineer).

Everything has been submitted to building control and we’re now waiting on their approval.

Me holding up a very long pole while the concrete sets!

While all of this is happening, we’ve decided it would be a fun idea to be able to keep an eye on build progress from afar as well as taking snapshots for posterity.

Our next door neighbours have set up a pole-mounted camera for this and we decided to do something similar. So last weekend, we went to the site and got hold of a few external timbers, some screws and “postcrete” (quick-setting concrete pre-mix for these situations).

After a bit of DIY-ing, we then mounted a battery-powered external camera and a solar panel to keep it charged, and then lifted the whole thing into a hole we dug, filled it with water and postcrete and waited!

For those of you interested in this setup, it consists of four 2×3 external timbers, each about 4 metres in length. One is sandwiched between another two with about half of the length overlapping, to give an overall height of around 6 metres. The final piece is cut to fill the gap between the outer two timbers in the lower half of the contraption. The off-cut from this can then be used to form a tripod-like support for extra strength. The whole thing stands in a hole around 1 metre deep filled half-way with water and then a bag and a half of postcrete.

Once this had set (around 10-15 minutes), we then surrounded it with stones, an earth mound and tripod-like supports on two sides. It leans to one side and sways a bit in the bracing coastal wind but so far, so good!

The camera is a Reolink Go paired with a Reolink solar panel. Due to there being no electricity or wifi on site, the camera has a battery that is charged by the solar panel. It also has a SIM card using Vodafone’s V-SIM service which charges a small monthly flat-fee for unlimited data, specifically for this sort of device. We use the Reolink app to watch the camera and take snaps, and I’m currently investigating how to automate the snapshot process so we can create a time-lapse video at the end.