Putting in a Loft Window

Words by Simon. See my blog entry for this page to share your installation experiences.

This is the story of putting in a loft window on 25th May 2000. The type of window installed is a Velux GHL 206 3000. See www.velux.co.uk.

1. Slate & Sky
2. Rain and Roof
3. Flash and Faff
4. Window and Windup

Slate & Sky

The job begins with a quick review of the instructions. I've already studied them the day before and everything seems to be quite straight forward. Hopefully we won't need to make the mid job trip to the hardware store that can easily halt progress.

After umming and ahhing about it for about half an hour, and checking the weather forecast, I finally start to cut out one of the rafters. The window I ordered fits exactly between the first and the third rafter and this hopefully makes the job easy. The vertical position at which to make the first cut is unclear, but I decide to go for the top end of a batten.
The photo at left shows me making the second cut, but at the bottom of the photo you can just see where the first cut has been made.

The rafter section actually comes away quite easily leaving the battens in place. The house was built in approximately 1880, I guess this is the original roof and it seems quite strong, and hopefully over-engineered.

Once the battens have been taken out we start to think about how to remove the slates. I thought that slates were held by nails at the top, but these ones turn out to be pinned to the battens at the middle. Armed with this knowledge I have a go at tilting back on of the slates from the middle of the area where we have removed the battens. It comes out fairly easily - once you take the weight off the nails that hold it it can be lifted over the nail head and withdrawn.
Getting that first slate out is a triumph, but doesn't let much light in yet.

It doesn't take long to make the whole in the roof a lot bigger, and the view is surprisingly good. (The picture doesn't do it justice.)

Rain and Roof

With the whole in the roof getting steadily bigger its time to check and double check just how this window frame is going to fit in. It seems that the slates have to be cut back some way to allow the frame to be screwed on to the rafters. The pictures in the manual are quite clear, but you have to study them a good few times before you are sure of the next step.

Well it looks as though we haven't made a mistake yet, and I give the go-ahead to Mark to remove more of the rafter and more battens - as these photos show.

The not very good photo at left shows the hole in the roof, while the weather was still good. We find that the slates can be nibbled away quite easily with a pair of pincers. The photo at right shows Mark doing just that - and behind him storm clouds brewing. It does start to rain a bit and we start thinking about getting a tarpaulin and maybe having lunch. But its only a shower.

With enough of the slates nibbled away we take the next step, which is to fit the angle pieces onto the window frame. These take a bit of measuring up, and we find that we can screw them completely onto one side before trying to maneouvre the window into place. The angle pieces are put onto the other side of the frame when it is in situ. This was a good idea as it means we didn't have to cut the slates back too far. The photo at left shows the frame neatly sitting on the rafters. We were very impressed with the design of the window and how easy it was to fit. Builders had told me that it was easy - but experience has lead me to be sceptical. The photo at right (taken on a timer) shows two happy installers ready for lunch.

Flash and Faff

With the window in place and lunch filling us up we're ready to tackle the flashing. The photo at left shows the top flashing piece - its quite big and I'm worried how we're going to get it in place. The photo below shows the problem - how am I going to tuck the flashing underneath the slates? - I have allowed the 60-100mm specified in the instructions. Actually the instructions don't tell me to start with the top flashing, but I've thought ahead and can see that this will be a problem.

We spend quite a while thinking about this, and I decide to nibble away quite a bit more of the slates. I do this to increase the gap upto about 200mm - nearly the width of the top flashing. All this is in vain because the flashing still can't be put in place.

I don't want to remove more slates above the window as the instructions imply. I figure that one way of doing it is to remove the window frame, put the top flashing in place and then re-fit the window. Reluctantly this is what we do, and it doesn't take that long to undo it all.The photo at left shows the damage I did to one of the slates. But the flashing now tucks under the other slates quite easily.

While I've been doing the flashing Mark held on to the frame, and you can see his strain left. The photo at right shows the reseated window frame. Second time around you can get the job done more quickly. We're lucky that we worried about the top flashing at this stage, if the other flashing had already been put on we would have had to either undo it all or think of another solution.

The pics above focus on the top flashing. I didn't take any of the other flashing because it was all pretty straight forward. The only think we had to remember was to cover the gaps in the slates on the bottom of the window before fixing the bottom flashing. For this we used some of the removed slate.

Window and Wind up

Well for two amateurs we were quite pleasantly surprised at how easy it all went! Well done velux for a simple design and good instructions. I am pleased that the window can be spun around the centre pivot as well as from the top - something that is a benefit, but not clear in your literature. The loft is very bright inside now, why did I wait so long to get around to this?

A couple of final photos to show the view from outside (click on these or any photo for an enlargement).