Category: Workshop/Studio

I had to carefully design the width of the windows, as there are a number of components to consider, as mentioned here.

So when it comes time to install a window, I need to put a ‘frame’ of 90x45mm timber around the window so that the weatherboards and window trim abut the window at the correct depth.

(note: need drawing here)

As you can see in this photo, I have installed the 90×45.

I chose to fix the 90×45 into the framing studwork behind the sheeting with 100mm screws, rather than nail it.

38x45mm cement sheet window trim will be fixed to this subframe, directly abutting the window frame, which will leave 45mm for the weatherboard fixing.

The second window to get built and installed is for the storage room. This window is more or less the same as all the other windows in the house. The difference between this and the window in the garden shed is that the sill has horns.
These horns extend the sill either side of the jams, and are mostly decorative in nature. Because the sill overhangs the weatherboards, the architrave cannot be carried across the bottom if the window. So the architrave must abut the sill, and the horns provide a place for this abutment.
I may choose to put an apron under the sill – I have not decided yet.

Prior to assemble, where the jams join the head and sill, I have applied two coats of paint to protect the timber.

 

 

 

 

 

The window is then assembled using three 75mm screws per joint.

 

 

 

 

 

 

 

Here is a closeup showing the drip groove cut into the front underside of the sill. This grove is cut with a few passes on the tablesaw, with the blade set very low (about 6mm).

 

 

 

 

 

Any holes, checks etc are filled with putty, then the window is painted with three coats of 3-in-1 undercoat/sealer/primer.

 

 

 

 

 

 

 

Just prior to installation, the exterior joint intersections are sealed with polyurethane to stop water seeping into the joints.

Installing the window is a case of sitting it in place, then shimming the sides to make it plumb. I am fixing the window in place with screws in the jams. I am screwing through the jams into the frame studs. The screws will be hidden bu the glazing/sash mouldings, so I have to take care to put the screws where the moulding wil hide them. The alignment shims are placed at the screw positions, and act to chock the jams where the screws go through so the jams dont get pulled out of shape.

Once the window is in place I put some architrave on the inside. As this is a store room I just used MDF architrave stock that I was given by a neighbour.

The garden shed window is the first window to be assembled, because its the smallest.
The core widow frame is just a sill and head, each with rebates to house the jams.

The head and jams are 221mm wide buy about 33mm thick. The only reason they are that thick is because thats the timber that was delivered to me, even though I asked for 25mm rough sawn. There is no point in making it thinner, other than surface planing to straighten the exposed face.

The jams have to be jointed together, because the timber is 190mm wide. So I need to joint on another 30mm. A real pain. It makes the whole process take so much longer. These joints are not using biscuits – I could not see the point. Also I am using Titebond III PVA glue rather than epoxy, so I can get quicker clamp-up times, and because I will orient this joint to the inside so it will not be exposed to the weather.

I am housing the jams into the rebates so to help eliminate twisting over time.

All the joints are getting two coats of primer/sealer/undercoat prior to assembly. I then use three 100mm type 17 screws on each joint.

In the case of this window I need to add an apron piece below the sill to match up to some existing brickwork on the shed. The apron was biscuited and glued on.

 

 

 

The whole frame will then get three coats of undercoat both inside and out. The reason for undercoating the outside (ie the bit thats hidden by the window frame) is to stop moisture ingress into the frame. Timber warps less if all sides are coated evenly.

I have finally started making windows, and the sills are the first step. This has been a long time coming, and I have a heap of work ahead of me for the windows. Before we started the house we had decided to make our own windows, because the cost of buying professionally made windows was just way too expensive. It was going to cost us $30,000 for double glazed windows for the workshop, and $39,000 for the house – and that was the cheeper end of the quotes we got. The most expensive was $60,000 just for the workshop!

We want timber windows. Primarily for the aesthetic, but also because of the thermal properties of wood. Whilst PVC windows are probably the best thermally, I do not particularly like them, and am not even sure if we could get BAL-29 rated PVC windows. Not a huge fan of aluminium windows either – they would not suite the look of the house, and we would have to get aluminium clad wooden wooden frames because AL is a terrible insulator. These would prove to be expensive also.

So, timber it is; and we must pick from a list of 7 timber species that have been fire rated and found suitable for BAL-29 and above. We have ended up with Silvertop Ash. Whilst in many cases it looks like Vic Ash, its much heavier.

The window frames need to be 221mm wide to suite the walls we are making. It works out like this:

• 10mm for plaster
• 120mm for studs
• 8mm for ply classing
• 25mm for exteriour foam insulation board
• 20mm for weatherboard batterns
• 38mm for weatherboards & trim

So the sills need to be 250mm to cater for the horns on weather ends of the sill that the window moulding will sit on, and to provide a weather lip over the weatherboards.

Each sill is made from two pieces of 140 x 45mm stock that is edge jointed together. I am using a router with a straight bit and a 24″ jointer hand plane to do the jointing. Then I put in two rows of biscuits to align them, however in hindsight one row would have been fine. The reason I say this is because when planing the bevel on the sill on some boards I exposed the biscuits because they were too close to the finished surface.

I am using a West Systems epoxy glue for the sills because the join will be exposed to the weather (under paint). I am finding the epoxy easy to work with because it has a relatively long open time when compared to a PVA like Titebond. However the disadvantage is a very long cure time in clamps (8 – 12 hours). With the clamps I have I can only clamp up 2 long sills at a time. Note that epoxy is a gap filling glue, so you do not need to clamp up as tightly as you do for PVA. I brush the epoxy on with a disposable brush.

Once out of the clamps the shaping can begin. I have made up a simple sled for my router that rides on a track consisting of an MDF base and two pine rails.

I am using a 3 horsepower Makita router, with a surface planing bit. The bit has 3 replacable carbide inserts, so I get 4 cutting edges per insert before I have to replace or sharpen the inserts. This bit and router combination work very well, and I get only very minor ‘tracks’ in the planed surface which can be belt sanded out.

Whilst I have a thicknesser capable of handeling this size timber, its no good to me because neither surface of the glued up plank is perfectly flat. So running it through the thicknesser would only produce a twisted board out the other end.

Therefore I sit the glued up stock on my sled base, and use small timber wedges to shim out any wobble in the board. Then I surface plane one face, flip it over and surface plane the other face. Once the first face is planed true, I could run it through the thicknesser for the other face. However I am already set up with the router so I just continue on with it on the other face.

To put the bevel on the main face, which is about 90mm wide, I use my electric planer to rough it in, then set a chock piece under one edge and again use the sufrace planer in the sled.

Then I need to cut out the horns at either end, and route a rebate at either end to house the jambs.

The rebates are cut with the router, using a straight cut bit. I again use the sled, clamping it in position on the table. I have fixed side rails to the sled that the router base runs up to, to control the width of the rebate. The rebate is cut only as long as the jambs are wide – 221mm.

I also hand plane a radius on the front edge of the sill, just because I think it looks nicer.
The final step is to cut a drip channe under the front edge using the table saw.

And thats how I make the sills.