Planning the build
Why build an extension?
Initial design sketches
On-line Building Regs
Meeting planners
 Meeting building control
 Planning the foundations
 Planning the floor slab
 Marking out the footings
 Damp proof course issues
 Possible drainage problems?

 Construction of the walls
 Proposed roof structure
Windows diary
 Window challenges
 Initial window plans
 Making the casements
 Making the frame
 Designing leaded lights
 Making leaded lights
 Assembling the window
 The little window

 The door frame
Demolition diary
 The demolition starts!
 The demolition continues
 Still more demolition

Foundations diary
 Foundation issues
 Drain issues
 Digging the foundations
 Rethinking foundations!
 Pouring the foundations

Floor slab diary
 Rethinking the slab!
 Floor vent extensions
 Preparing the slab #1
 Preparing the slab #2
 Pouring the slab

Walls diary
 Preparing to build walls
 Build up to the DPC
 Build the walls #1
 Build the walls #2
 The gas men cometh
 Build the walls #3
 Finishing the walls
Roof diary
 Roof structure build
 Tiling the roof
 Finishing the roof
 Finishing the gables
 Roof insulation

 Floor screed
 Shower room
 Shower room floors
 Shower room walls
 Utility room
 Utility room walls
 Utility room floor
 Finishing the windows

Project finished!
 Final inspection
 The certificate
 Final thoughts

 Twelve months on!
 Material costs
Sister sites
 House re-roof project
 Home gas usage data

 Stop paint flaking
 DIY secondary glazing


Making the wooden casement frame

Now that the casement windows are pretty much built, it's time to build the frame out of 69mm by 94mm Redwood par. I bought four 2,4 metre lengths.

Wednesday 7th March: Six lengths of wood are required - four uprights and a top and bottom. So the first task was to cut them roughly to length using a cross cut saw leaving sufficient to correct any error.


Here are the six pieces laid out in the respective positions on top of the three casement windows.
I then needed to route out the rebates when the casement windows fit into the frame - these are roughly 16mm by 69 mm. The end uprights only need one rebates while the two inner uprights need two.
When I've done this in the past I used a bench circular saw but they always seems to go a bit wonky so I decided to use a router this time. I'm not sure the result is any better though!
This picture shows one of the centre uprights in place between two of the casement windows and show the two rebates.
This picture shows one of the two outside uprights with only one rebate.
This shows the inside upright in place butting up to the bottom of the frame showing what the completed window will roughly look like.

Next comes the joints!
Sawing the eight mortise and tenon joints. This is the time to be very careful as it's easy to make a mistake. I did four joint first and then fitted the casement windows to ensure I got the height correct.



After marking up the position of the tenons on the bottom cross piece, I use a flat bit to remove the majority of the wood in the four holes.


This is the joint on one of the outside uprights.


I then used a chisel to clean the holes ready for assembly.


This is the casement frame roughly assembled to check that it all fits together correctly - it does!



This is the frame with the three casements inserted. After cleaning the joints, the next task will be to glue the frame making sure that everything is square.



Saturday, 10th March: Four sash clamps were used to clamp the frame together after gluing - I used liberal amounts of glue!

It's important to make sure that everything is square as it will be too late when it dries.

This activity, amazingly, took a couple of hours!

Saturday, 10th March: This is the frame just after removing the sash cramps. Every thing seem to be square and the casement windows fit well.

The next task is to clean, sand and router the chamfers on the inside frame. A task for another day!

The frame is now sanded.

Sunday, 11th March: After sanding a few holes and knots are filled. The last task is to chamfer the inside edges to match the three casement windows.
I've marked the points where the chamfers are supposed to end.

a Router is used to create the chamfer. There is no chamfer on the bottom of the widow as i will be adding a small sill later.


The chamfer on the frame matches those on the casement window.



The frame pretty much completed except for the inside sill

The frame has now been painted with aluminium primer

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