window section advice please

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RogerM

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We have 2 side windows in a gable end which will be difficult to reach after an extension is built. They are 30 yrs old and rotting - not badly - but never-the-less the time to replace them is now rather than when they are difficult to reach.

They are each single sash windows, 1180mm x 490 mm, hinged down the RHS as you look out from the inside. They will need to be on easyclean egress friction hinges because it will be difficult to reach them from outside, and the current windows which are simple casements suffer from flies gathering in the gaps around the edge which then cascade into the room when the window is opened. I therefore plan to replace them with European Oak storm proof sashes with a 5mm Silplex bubble bead between the overlap and the frame to prevent flies getting in to the gap, and with the back of the sash sitting on an Aquamac 63 seal. Locks will be high security shoot bolts.

I am planning to use the same laminated construction method as I've just used on my back door, partly because I'm familiar with it, and partly because this will have to be done on a router table as I have no spindle.

Here's the section I thought I'd use.

Window%20section%20%20001.jpg


Any constructive comments please from those who have experience in this field?

The glazing will be Planitherm Total+ 4/16/4 set with a warm edge spacer, and which should give a U value of 1.1. We rely on this side winmdow a lot for morning light (it's east facing) so want to keep the section width to a minimum, although thickness isn't an issue. The drawing as shown provides for a thickness (inside to outside) of 75mm, and a frame width (wall to sash) of 60mm (max) along the bottom, and 45mm up the sides and along the top. Glazed unit will be installed from the inside for security and also for ease of weather proofing.

What's the current thinking on trickle vents. I've been looking at windows in showrooms and there is not a trickle vent to be seen anywhere. My own view is that if we don't have to have them, then let's not.
 
The design looks awkward in use.

What you have designed makes a heavy window frame which opens outward. It will be very difficult to remove for maintainance. Such windows tend to cause an excessive use of foul language repeated every few years. Especially if they are hard to reach from the outside.

In my oppinion there are two slightly better ways to do this.
1. A window with two separate window frames. One glass in each. The inner frame opening inwards and the outer opening outwards. Each frame fits into a simple rebate in the sill. If the sill is made wide enough, let's say 6 inches there will be a lot of air between the inner and the outer glass and that gives a reasonably good U-value and sound insulation despite the simple design. This is the classic style of windows in Finland. The frames become light enough in weight for easy handling. This kind of windowas are easy to make with basic tools. Right now I am making a couple of them for a customer.
2. A window that opens inwards. Normally it would have a separate frame for each glass. Both frames are independently hinged in the sill. The inner frame fits i a simple rebate on the inner edge of the sill and the outer frame goes against some thin boards glued to the outside of the sill. This style is a bit easier to clean and you can reach every part of it from the inside. The design becomes much more complicated that the classic style but only a wee bit worse to make than your design. This kind of windows tend to be more difficult to get tight and tend to rot fastyer than the classic style. The U-value becomes the same as my previous excample.

Oak is known for containing some chemicals which cause unreliable glue joints. Personally I avoid glue joints in the weather exposed parts of a window as far as possible.

Well.....I have a lot of oppinions and none of them are absolute truths.
 
It has been over a year now since I made any windows. However, I can say your section drawing looks good. Apart from the rebate in the frame. Why is it stepped? When I used to make espagnolette windows, the rebate in the frame just had a groove in a flat rebate. Also, I don't see the need for a drip groove on the casement either. That's my opinion on it, however you are probably using a locking system that's completley different to the ones I've come across.

This link may be of help to you: http://www.boylandjoinery.co.uk/cad_sections.html
 
Simon - that's a really helpful website - thanks. I've stepped the bottom and top rails to allow for the 13mm stack of the egress and easyclean friction hinges I'm planning to use. Without the step I can't see how there would be room for the hinge as the window opens. I'm waiting for the hinges to arrive from Reddiseal and will have a play around with them before cutting the section.

Having never made a window before I'm starting with a single sash, and will make an example in soft wood by cutting up some old 4 x 2 I've got lying around before making the real thing in oak. Enjoying the learning curve at the moment!

heimlaga - thanks for your ideas. It's always interesting to see how things are done in other countries. However, this not only needs to pass UK building regs, and also my boss's requirements (SWMBO), who insists that the window be easy to clean from the inside. It also needs to fit in with the style of window in the rest of the house - so a single outward opening sash is a must.
 
Trickle vents are an abomination IMO. If you don't have them in your current windows then you don't need to fit them in your new ones.

If you need ventilation then open the sash 1/4" !
 
RogerS":3mcy9nad said:
Trickle vents are an abomination IMO. If you don't have them in your current windows then you don't need to fit them in your new ones.

If you need ventilation then open the sash 1/4" !

Thanks Roger. My sentiments entirely. And we have no condensation problems at the moment.
 
I made the windows and French doors for my last house and the LBO was quite happy for me to have trad air bricks rather than the trickle vent abomination aforementioned.
 
Austin Branson":248h20in said:
Hi, Roger, I am shortly to start an Oak timber framed extension to my house, and will almost certainly making my own windows, too. Can I ask - how did you get on?
Many thanks,
Austin

Which Roger?
 
Hi, Roger - it was actually addressed to RogerM, but I would welcome any advice from yourself also. I will shortly be building a traditional oak timber-framed extension. I have been advised to use 'steady' oak, as the movement of green oak would be too active to consider DG units. My question at this time is twofold - I could use some help designing the profile of of the frame and casement of the windows (I am thinking top-hung), and then a question of how to install the new windows between the frames (ie should I cut a rebate on the sides and top to effectively reduce the members to 24mm - to match the DG units - and install in the same way as the DG units? or fit them between the oak stiles, and install fillets internally to hide any gaps, improve air-tightness etc). I will almost certainly be posting questions later, on suggestions of how to make the oak frame itself airtight, as shrinkage will inevitably introduce gaps, both at the joints, and where timbers bear on masonry.
Looking forward to hearing from you,
Austin
 
Austin Branson":u0k8sv6r said:
Hi, Roger - it was actually addressed to RogerM, but I would welcome any advice from yourself also. I will shortly be building a traditional oak timber-framed extension. I have been advised to use 'steady' oak, as the movement of green oak would be too active to consider DG units. My question at this time is twofold - I could use some help designing the profile of of the frame and casement of the windows (I am thinking top-hung), and then a question of how to install the new windows between the frames (ie should I cut a rebate on the sides and top to effectively reduce the members to 24mm - to match the DG units - and install in the same way as the DG units? or fit them between the oak stiles, and install fillets internally to hide any gaps, improve air-tightness etc). I will almost certainly be posting questions later, on suggestions of how to make the oak frame itself airtight, as shrinkage will inevitably introduce gaps, both at the joints, and where timbers bear on masonry.
Looking forward to hearing from you,
Austin

Austin. - just picked this up on my tablet whilst travelling through Laos on my way to Vietnam and Cambodia, so a bit difficult to offer a lot of help. My project was for 2 sets of bifold doors, 3 single windows, plus a double and triple. I wrote up how I made the singles on this forum, and also the bifold doors. Just do a search on bifold doors with windows- a first attempt. - to see how I went about it. If you have not made windows before i strongly recommend making one in softwood as a sample first - it taught me so much and saved a fortune.

I was installing side hung windows in a traditional block extension so not a lot in common with what you are planning. I would suggest agreeing design with building control at an early stage and if possible use one of their private subcontractors. We used jhai and found that common sense prevailed on all important matters inc that of tricklevents. I.e. not needed so long as you have lockable night latch. Good luck.
 
Hi, Roger,
As a matter of fact, I posted a similar question on that forum last month, and although the replies were very helpful, I am still a long way off a design.

Could you suggest where I might look for a section design? I have looked for books, but failed to find one that looks suitable that I can afford.

Many thanks,
Austin
 
RogerM":1hm5d5bc said:
Austin Branson":1hm5d5bc said:
Hi, Roger - it was actually addressed to RogerM, but I would welcome any advice from yourself also. I will shortly be building a traditional oak timber-framed extension. I have been advised to use 'steady' oak, as the movement of green oak would be too active to consider DG units. My question at this time is twofold - I could use some help designing the profile of of the frame and casement of the windows (I am thinking top-hung), and then a question of how to install the new windows between the frames (ie should I cut a rebate on the sides and top to effectively reduce the members to 24mm - to match the DG units - and install in the same way as the DG units? or fit them between the oak stiles, and install fillets internally to hide any gaps, improve air-tightness etc). I will almost certainly be posting questions later, on suggestions of how to make the oak frame itself airtight, as shrinkage will inevitably introduce gaps, both at the joints, and where timbers bear on masonry.
Looking forward to hearing from you,
Austin

Austin. - just picked this up on my tablet whilst travelling through Laos on my way to Vietnam and Cambodia, so a bit difficult to offer a lot of help. My project was for 2 sets of bifold doors, 3 single windows, plus a double and triple. I wrote up how I made the singles on this forum, and also the bifold doors. Just do a search on bifold doors with windows- a first attempt. - to see how I went about it. If you have not made windows before i strongly recommend making one in softwood as a sample first - it taught me so much and saved a fortune.

I was installing side hung windows in a traditional block extension so not a lot in common with what you are planning. I would suggest agreeing design with building control at an early stage and if possible use one of their private subcontractors. We used jhai and found that common sense prevailed on all important matters inc that of tricklevents. I.e. not needed so long as you have lockable night latch. Good luck.

Now that's a real 'drive-by' gloat ! Can you please bring me back some nice exotic hardwoods ? About 2m long boards, 1" thick would do nicely. :D
 
Austin. - just picked this up on my tablet whilst travelling through Laos on my way to Vietnam and Cambodia, so a bit difficult to offer a lot of help. My project was for 2 sets of bifold doors, 3 single windows, plus a double and triple. I wrote up how I made the singles on this forum, and also the bifold doors. Just do a search on bifold doors with windows- a first attempt. - to see how I went about it. If you have not made windows before i strongly recommend making one in softwood as a sample first - it taught me so much and saved a fortune.

I was installing side hung windows in a traditional block extension so not a lot in common with what you are planning. I would suggest agreeing design with building control at an early stage and if possible use one of their private subcontractors. We used jhai and found that common sense prevailed on all important matters inc that of tricklevents. I.e. not needed so long as you have lockable night latch. Good luck.[/quote]

Thanks for coming back, Roger. I have looked at your thread 'Windows - a first attempt', and I am inspired. Unfortunately, it has generated a lot more questions:
Did you mill up each of the laminations yourself, or buy it already milled?
I want to use traditional casement storm-hinges, top hung, any thoughts?
I have looked at the Boyland spec, and it seems to show a single seal on the bottom rail, and two on each of the stiles and the head - any idea why only one on the bottom rail?
I have never used seals - which ones did you use? Did you go the same (1 on the bottom, 2 on the sides and the head), or something else.
Presumably, you fastened your espagnolette bolt to the slam side of the casement - should I mount one on the bottom rail? I am concerned it may not be possible.

No help to be had from 'Building Control' I fear. I applied for planning permission using a company who specializes in translating for English folks, and completing complicated French application forms; when I asked for guidelines on building reg's, I was told there are none. I will be responsible to ensure it does not fall down within 15 years, and that's about it.
Thanks again,
Austin
 
Austin. - hadn't noticed your address in Normandy. At least you don't have building control to send a jobs worth to worry you.

I dimensioned my own timber from sawn 25mm and 37mm on my p/t.

Sorry. - have no thoughts about top hung storm hinges. Beyond my experience I'm afraid. I used friction hinges as shown.

Re the seals - I'm guessing that only one seal was used on the bottom to allow drainage. I only used one seal all the way around - aquamac21. Had no problems and decided that additional seal was not necessary.

Can't see any problem with mounting an espag bolt to the bottom. TIP - try to get one with an inset of at least 25mm instead of the standard 22mm. If you make a sample as STRONGLY RECOMMENDED using cheap soft wood you will find out just how big a difference the extra 3mm makes. Also gives you the chance to play with different hardware when finish doesn't matter.

Hold that helps.

RogerS - sorry, couldn't resist the gloat. Sitting by the river at Vang Vieng with a g&t with a temp of 28 deg. How about you? Seen lots of teak stands. Photos on my return. Watched a guy cut some wood on a table saw with no guard or riving knife, and with a Buddhist monk in his orange robes sitting cross legged on the extension table about 40 cms from the blade. You couldn't make it up. Photo evidence to follow on my return.
 
RogerM":28lx92ay said:
Austin. - hadn't noticed your address in Normandy. At least you don't have building control to send a jobs worth to worry you.

I dimensioned my own timber from sawn 25mm and 37mm on my p/t.

Sorry. - have no thoughts about top hung storm hinges. Beyond my experience I'm afraid. I used friction hinges as shown.

Re the seals - I'm guessing that only one seal was used on the bottom to allow drainage. I only used one seal all the way around - aquamac21. Had no problems and decided that additional seal was not necessary.

Can't see any problem with mounting an espag bolt to the bottom. TIP - try to get one with an inset of at least 25mm instead of the standard 22mm. If you make a sample as STRONGLY RECOMMENDED using cheap soft wood you will find out just how big a difference the extra 3mm makes. Also gives you the chance to play with different hardware when finish doesn't matter.

Hold that helps.

RogerS - sorry, couldn't resist the gloat. Sitting by the river at Vang Vieng with a g&t with a temp of 28 deg. How about you? Seen lots of teak stands. Photos on my return. Watched a guy cut some wood on a table saw with no guard or riving knife, and with a Buddhist monk in his orange robes sitting cross legged on the extension table about 40 cms from the blade. You couldn't make it up. Photo evidence to follow on my return.

Thanks for that Roger, can you tell me where I should be looking for quality espagnolette hardware, please?
Regards,
Austin
 
I used some provided by Westward Building services of Saltash. Sorry I can't be any more precise as I'm still swanning around SE Asia. However if you give them a ring and get their catalogue the espags I used specifically state that there is a choice of 22 or 25 mm insets. If you haven't tracked them down by 12th Feb I'll be back home and can check the actual ones I used but as Westward don't have a website and I haven't taken their catalogue on my travels I can't be more specific at the moment.
 
I've now had a look at what I installed. These were Excalibur Dual Claw Locking Shootbolt. I don't know where you would buy them in Normandy, but I got mine mail order from Westward Building Supplies where it appears on p48 of their catalogue, issue 3, under Excalibur Shootbolt System. No doubt a telephone call to Kenrick would tell you who else they supply. They are very easy to fit and a bit more substantial than a standard espagnollette system. These sit in a standard Eurogroove which you can cut with either a hand held router or on a router table. If you have more than one window to build it is definitely worth buying the cutter. Practice on your experimental trial window in softwood.
 
Austin

If you are glazing a green oak extension look at face applied glazing systems. You can easily fit a opening casement in to the system they just need to have a profile added to the frame. We have a local jionery firm manufacture any openers we need. We use the same profile on door frames too.
 
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