This is the frame elements cut to size by Crowes Saw Mills, Mohill, Co. Leitrim, ready to go on site.
IMPORTANT ! You should look through these photos with the building instruction drawings to hand.
Preparing the site. Topsoil stripped, hardcore to road.
Marking the site. See the drawings about how to do this, it is a job for two people. The notion of tolerance is important in building. Tolerance refers to how accurate you need to be, for example when cutting a piece of timber for the frame you would need to be within a millimetre or so of the correct size, however when digging a hole for the foundations you need only be accurate to within one or two centimetres, if it is a little bit out then it just means that the timber column will be a little bit off centre which is no big deal.
Marking out the site, you will need a long tape, timber stakes, special string for marking out, (special because it doesn't stretch, buy it in a hardware shop). This is a great thing to do, as you are literally drawing the plan onto the ground, abstract drawings are becoming reality...
A mini-digger is big enough for this job.
This is a completed foundation, the top should not be 100% level, it should slope a bit towards the edges so that water won't pool on it. With regards to tolerance whilst the edge of the concrete does not have to be super accurate, the galvanised steel brackets must be accurately positioned to within a few millimetres, since you must do this job quickly before the concrete is dry, set up all the stakes before the concrete pour ready to re-attach the string to, have a few hands to help you and ask the concrete supplier for a slightly wetter mix.
This is a stack of floor beams which are having joist hangers fixed to them. You need ok weather to do this comfortably unless you are lucky enough to have space under cover, in a barn, polytunnel or a shed for example.
The frames are stacked ready to erect. Notice the Flashtex stuck to the bottom of the columns. Flashtex is a heavy duty self adhesive waterproofer - it stops damp from rising up the timber column from the concrete. Some people use lead for this instead. I used one layer of lead layed on the foundations and one layer of flashtex stuck on the columns to be sure to be sure. Each frame is heavy, this day or two of erecting needs a big team, maybe about eight people. This is a good time to get help from any carpenters that you know, its an exciting stage of the building process so its quite easy to get help.
Frame ready to sit into foundation bracket.
Two left to go. We stacked them on old truck tyres to get them off the ground.
Frames in position with cross floor beams. See the temporary cross bracing to keep the frames steady.
Running right to left are the main beams that have the joist hangers prefixed to them - sitting into them are the joists.
Once the frames and joists are in place you can start to erect the walls. Note the double beam at the bottom which supports the wall studs, the outer one sits on the little shelf formed at the bottom of the column. I used small fixings from bat metalworks to fix these verticals, a carpenter would normally skew nail them. They must be fixed front and back to stop them from twisting.
Basic framework, this was how it looked after one day of frame erection.
Basic framework. This photo gives you the overall idea!
Basic framework attached to foundations. Notice studs left out to accomodate double doors on left hand side. The smaller windows fit in between the studs.
Detail of basic framework and upper floor. The top horizontal member is layed flat. Each roof beam will sit exactly above each wall stud so the weight is transferred straight down.
Detail of basic framework and upper floor. You can see the wall studs sitting on the double beams below.
Detail of vertical uprights.
Detail of vertical uprights.
View looking up at roof beams.
Here you can see the start of the roof being constructed. Each roof beam is identical, you have to make a template and then cut each one. Notice a temporary diagonal for strengthening during construction.
Roof beams in place, notice one wall stud missing in the middle where the porch will be. The top member is strengthened in this area.
This photo shows the end wall studs which sit within the main frame.
We temporarily sheeted the south end with plywood, where the big windows will be. This keeps the frame strong during construction, we removed it when we were ready to fit the glass.
Upstairs dormer window. Three roof beams were left out to accomodate the dormer. It took quite a lot of messing to get the dormer right, off-standard elements like this take much more time than the modular, standard elements of the building - the dormer probably took as much time as the rest of the roof put together, this really shows just how quick modular building is!
Here are the panel vent racking sheets being fixed to the wall studs and the roof beams. Panel vent is a breathable material and comes in sheets 2400mmx1200mm, this is why the whole frame is on a 600mm grid. The sheets did not need cutting ( apart from around the off-standard dormer), as you can see, the walls are the height of one sheet layed vertically and one sheet layed horizontally. the roof is a bit higher than one full sheet, so a bit of cutting is needed here, sorry!
Gable in panelvent racking. It gets nailed to all the timber members. Racking triangulates the structure, making the walls and roof stiff.
The roof joists are tied down to the wall studs with galvanised straps which are fixed through the panelvent.
Interior view. Double door on right, temporary plywood to large south facing window.
The breather membrane goes on next. It keeps water off the panelvent while allowing water vapour to escape from the building when complete. The green surface of the panelvent keeps it dry as well so don't panic if a shower of rain arrives, it will dry out. Check the manufacturers specification to see how long panelvent can be wet before it loses its strength. The breather membrane is fixed with staples.
Rear, breather membrane going on with staple gun. It needs to be stretched tight.
Rear, breather membrane going on.
Interior showing first floor floor joists.
Upstairs interior, panelvent closing it in.
Front breather membrane complete. The battens go on top of the breather membrane and will take the Onduline cladding.
Onduline on front, notice the spacing of the battens based on the Onduline manufacturers specification. See elsewhere for details of flashings around windows!
Onduline on back. Though you can fix Onduline with specially supplied nails, we used Tex screws. These are more expensive but do a much better job, they are easy to take out if you make a mistake.
This photo shows the interior after the insulation was fitted, and the interior air-tightness/ vapour barrier was fixed. The best product to use is Intello. It is fixed with staples and taped at the joints with a special tape. The walls are then battened out to take the plasterboard. The space behind the plasterboard is used for electrics and plumbing so that you never need to pierce the airtightness membrane.
Plumbing and wiring.
Window frame and cornice are formed using the cardboard edges used for packing pallets. This means that the rough edges of the plasterboard are covered without having to skim the building.