I've mentioned my extension refurb plans/confusion on other threads, but I now have building warrant and I am pulling the trigger on order of Russell Timbertech, Timber framed triple glazed sliding doors (u=0.7) and windows (u=0.9). As mentioned before I've struggled to get builders/joiners that are competent, willing and available, so long story short I am on my own with this, with a large pinch of figuring it out as I go along.

I feel like I have a reasonable quote from Russell, and it looks like a decent quality product, but communication with them hasn't been the best, and I thought I might be better to just to see if anyone on here has installed their sliding doors and windows before?

Basically, what I am trying to find out is how they are installed, in case I need to take anything into account for the final measurements. The installation instructions seem to infer that there are pre-drilled holes through the frame, but its not clear if they are pre-drilled or if you have to drill them and I can't seem to get any clarity from them on this. Its important for me because the doors will be 145mm in section, while the timber corner post and lintel that they will fix to are only 150mm and ~110mm respectively, so I need to have an idea where the screws will go in case they are going to come through somewhere where there is nothing to fix them to. For example, the post seems to line up with the inner leaf/cavity, so it looks like the window will end up part way across the cavity and mostly on the inner leaf, but if there are screw holes and they come through into the cavity, or they come up an miss the lintel, then I need to account for that in advance.

I am presuming in all of this that timber doors and windows are installed in much the same way as uPVC, i.e screw them in place with packers at the screw locations and then fill any gap with low expansion expanding foam? Or is there a better way?

Sorry of the rambling post, hope it makes sense, and if anyone has fitted these before I'd appreciate any insight.

Thanks very much GreenPaddy.

Do you mean this sort of thing? - https://www.screwfix.com/p/sabrefix-heavy-duty-angle-brackets-galvanised-40-x-60mm-25-pack/71671

Right. That actually sounds quite good and will probably help with fitting as one door is apparently 230kg. No need for packers then, just make sure its going on to a level surface at the threshold, move into place and screw to the wall on one side and the post on the other, then fill the gap. I'd imagine some spacers under the brackets if needed to ensure it is straight up and down.

Its actually brick inner and outer leaf on one side of the door, with blown in EPS cavity insulation. Not sure how it is closed. On the other side where the window meets the corner it is a timber post. The timber post is currently on top of a dwarf wall, but I am removing the wall and replacing with a full length timber post (currently windows and wall being cut out to fit doors). The timber lintel appears to be two 50x200 pieces, with about 10mm gap in the middle so about 110mm depth. This looks like it is suspended at the top of the cavity on the wall side and sits on top of the timber post at the other side. My amateurish drawing attached might explain this better.

If using brackets that is handy as I could just fit a bracket deeper in on the door to account for the fact that the lintel position is further in, and then put insulation and plasterboard over the timber lintel from the inside to hide the bracket.

The other door, which runs from in the adjacent to the first door from the timber post, has what appears to be solid block on the other side, and a narrower single 50mm thick lintel (not really carrying any weight), so again the brackets would help as I can position them on the frame appropriately.

djh mentioned brackets on another thread but I didn't really click as to what was meant until now.

Not completely sure what you mean by this part "Think about the exterior and interior reveals, how they are close to the window/door frames, and Russ TT window cill depth, which will determine exactly where the window/door units should sit within the wall construction.", but the window cill is one thing I am trying to get details on from them. We currently have concrete cills, and were thinking of keeping these and maybe somehow cutting the cill on the inside at the cavity to thermally break, but not sure if the window can come without a cill. The windows are a more straightforward proposition as it is masonry all around. I am presuming that inner leaf is the best position as for various reasons our insulation will all have to be internal. According to the guys who did the cavity insulation the bit where the windows are (kitchen and utility room) are solid block.

Thanks for this djh.

I'm presuming that the weight is on the bottom. They don't specify this but from the drawing it looks like the roller is on the bottom. I am thinking of taking the wall down below floor level, then pouring or skimming the wall at that part so I have a perfectly level surface. I was also thinking of building it up from there to the required level with compact foam (as suggested on another thread). The recommended stress for compact foam is 1.01 N/mm2, and if I have my calcs right this is 2940x145x1.01=430563=430kN~4300kg, so should be well able for this door. They have just told me that they have discontinued the hardwood threshold I had spec'd and it is a low level threshold now so will need to be positioned not much lower than finished floor level. I am planning to raise the floor level with insulation so I need to factor all this in with the measurements.

Due to the time I have I am going to have to prepare the opening etc while I am off in later September, then close it up temporarily until the doors arrive. My plan is to have people over to help me in with the delivery and bring the door inside, then prep everything, get brackets on, then get some people back over to help lift in place a couple of days later.

I have a couple of glass suckers, but hadn't thought I would need these. I got the impression that the door was to be lifted by the door jambs only. Am I missing something here?

I know this might be a daft question, but any recommendations of how many people to lift? I've got to get it up a couple of steps then about 30m to the back of the house. I was working on the impression that 320kG was about the weight of an old cast iron inside upright piano, which I have moved before with two people, but in this case due to the height and tip risk I was thinking to have an extra one or two people to each side to steady. Does that sound like enough?

Recently I fitted two fold and slide doors 1@ 4M and 1@ 3M and I echo what djh says regarding leveling.
Both these doors were combination top hung/bottom rolling and with adjustment. Nevertheless I took great care in calculating FFL especially the 4M one, as it separated the living room from the sun-room and I didn't want any sort of FFL difference. I also had to ensure the bottom track sub-base and the overhead Glulam beams were perfectly parallel, I would think this will be important to you too.
I can't answer for your compact foam because I put in a steel box section base on the room divider doors with the supplied track sitting on it. Having a full length and true, rigid, sub base helps with leveling. The smaller exterior door is sitting on brick.
What PiH says is right, use webbing straps under large heavy sections with someone at each side, and someone else keeping the whole job vertical. It's a method I've used frequently for large glazing, I use 80mm wide webbing.

I've never dealt with RT but their credentials and workmanship seem to come with high praise on this site. I can't say if that's justified or not. As an a outside observer however, and one who's been in the interior re-fit and re-furb business for many years and a qualified cabinet maker, and having dealt with 100s of companies over the years , they wouldn't have got past first base with me.
I looked on their website and I couldn't find tech drawings or timber sections or details of running gear etc. etc.. I looked through downloads and if they are there, then they aren't easily found. it's one of the first things I look for.
It could be my ineptitude on the computer, but some companies do give tech specs etc and if they don't then warning bells ring with me. It could be that they change hardware suppliers regularly and are unable to commit to drawings which leaves you a bit adrift with checking suitability.
There are 100s of small companies with facilities for window manufacture and lots of them use the same spindle moulder tooling and same widely available laminated timber, likewise hardware, so why not supply drawings online,- strange, IMO.

Owlman - I've been frustrated by this aspect of RT too. Not having experience in this area I just presumed that was how things worked in this industry, but I have since found other companies websites who have a multitude of drawings/installation info, even videos etc freely available for download.

Not having experience fitting doors and windows it was even more critical that I had drawings, as I figured that with drawings my experience as an engineer, general info available online and the knowledge and support from GB forum site I would be able to muddle through. As it stands I have an order that references a ~40mm hardwood threshold, an email that says this is discontinued and they now only do 19mm thresholds, and a drawing attached to same email that seems to indicate the threshold is actually 27mm, and I obviously can't even finalise dimensions until I know which it is, and there are a few questions about the windows that are also holding out finalising dimensions.

To be honest its hard to even get a decent picture of the products online and we had to visit their showroom to satisfy us with that aspect. My impression is that they are just an old fashioned company that haven't completely caught up with the idea of having an online presence but I am hoping that now that I have paid I will have better access to technical/production, to finalise the details, otherwise I'm in trouble! :)


Nick - thanks for that, that's reassuring. I'm considering using this, but as the room concerned is raised with respect to ground level I am now starting to think that going for the extended cill and running perimeter insulation all around might be the better option. Good to have options.

Thanks Owlman. Good tips, appreciate it, i'll look into this. I know the answer to some of this; for example i've been told its an aluminium/painted pine low level threshold, and I know that the adjustment is on the bottom roller, although the fact that the installation guide directs you to only adjust that one would indicate there is another adjustment. Their date sheet states "aluminium vented bottom bead". I have some drawings now so I can look over and see what I can gather about the other stuff.

They have told me that everything comes fully assembled except for the ironmongery, hence the 230kG weight of the largest door. Unless I can get specific details and assurances I plan to ask if I can collect and get them to load into the van. This would probably be the better option for me as I can reverse a van with a tail-lift right into my drive and use the tail lift to take the front steps out of the equation. I can also collect them on a Friday and leave them in the van until a time at the weekend that suits to get enough bodies together to unload and install, with everything prep'd in advance.

Check what the compressive strength number means. I think it will show you an allowable compression at that load, say 10%. If at the given load, you are ok with the insulation compressing/dropping by the relevant amount then it's fit for purporse. If the drop from initial installation over time would make the door threshold loose, then it's not ok.

Fixings for the bottom rail may also be a issue? Even repeated walking on a poorly fixed threshold will see it springing after a short time. That's not something that's easy to remedy, with hard floor finishes either side of the threshold.

This is something I've personally never really gotten a solution that I'm 100% happy with. As to running the insulation from floor through the threshold and beyond, the waterproofing detail may be the sticking point (ie. rain at the foot of the door tracking in on the insulation).

Logically, what is needed is a very hard material, that doesn't deflect, and can take fixings, that also has great Uvalues, and hence these expensive, very hard, foamglass or compactfoam products.

If anyone has a great, simple to install detail, I'd gladly steal it

I found this for celotex

compressive strength = CS(10\Y)140

I'm thinking that means 10% compression at 140 kPa. So 100mm board will compress 10mm at that load. Good luck working out what that means in everyday use, and treading on it over years.

You could just bite the bullet, and buy some foamglas, lay a block under each threshold, and it can sit on either side of your DPM, depending on how you want to do your detail. Probably work out about £20/door. Will never pay bay in energy terms, but stops the cold floor at the door, maybe even some condensation.

I keep intending to try it out, but much better if you do it, and tell us if it works, and what mistakes we can learn from...

Posted By: GreenPaddyI'm thinking that means 10% compression at 140 kPa. So 100mm board will compress 10mm at that load. Good luck working out what that means in everyday use, and treading on it over years.

If I am working it out right that would require a door of around 6000kg, but I suppose the issue is not how much it would take to deflect by 10%, which is obviously too much, its probably how much force would cause it to deflect at around 1%. Looking at the compactfoam data their recommended maximum force applied is 1n/mm2, which is less than the figure of 1.91n/mm2 quoted for 2% deflection. I don't mind paying the extra for compactfoam if needed, none of this stuff will ever pay back, just trying to understand. I don't really know anything about foam glass so will need to look into that.

Posted By: gravelldWhere are you Kenny? I have some Compacfoam left over, about 4m of the 50mm depth.

In Linlithgow, West Lothian.

@Kenny, Green Building Store do CompacFoam 200 in 100x150x1000mm sizing

I ended up going for the compacfoam for this, so thanks bhommels for pointing me back there. I bought a table saw and with a little modification - i.e. removing all the safety features, guard etc :) - I was able to cut along the 150mm section by making two 75mm cuts on each side to get two pretty even 150x50 blocks for each 150x100 piece. Very impressed with this stuff. Hard to believe that something so rigid/dense would also have a thermal conductivity of 0.046 W/m.K, and it cuts fairly well with the table saw, just a little melting in parts.

My next step is to get it level so that when the door arrives it should go straight on without need for adjustment. There is a PDF on the compacfoam site which seems to show it being fixed to the bottom of a door threshold, shimmed, then the gap filled with what looks like PU foam. Was a bit sceptical about this as it doesn't seem to make sense to be going for something with high compressive strength, then sitting it on top of foam, so thinking I will probably bed it in mortar, not sure what others who have used this have done to level?