How to Install a Velux Top Hung Roof Window on a Profile Tile Roof - Part 4

Installing the EDW Profile Tile Flashing and Finishing the Window Installation

In this 4 part guide, Mark - A Velux Technician takes you through the full installation of a Velux GGU Centre Pivot Roof Window with a White Polyurethane finish. This window is being installed onto a plain tile roof so we’re installing an EDP Flashing Kit and BDX Insulation Collar.

In Part 4, the final part of this guide Mark begins the installation of the flashing kit, the EDP Flashing kit allows for the window to remain completely waterproof while using Interlock Redland 49 Tiles. Once the flashing kit is installed, the sash is reattached to the frame, completing the installation.

View the other parts here:

Part 1: Unboxing and preparing the window for installation
Part 2: Installing the BDX Insulation Collar and fitting the Window Frame
Part 3: Underfelt collar and Transverse Drainage Gutter Installation

Video Transcription

Understanding the box labels

Now it's time to fit the external flashings and claddings to the window. As you can see from the carton label, it's a very similar layout to what we've seen up to now on the window and the installation products. Our first one line is referencing the type of flashing and the type of roofing material it can work to, but you don't need to understand the coding. As we've mentioned before, we have a graphic here which is showing you it is predominantly used for interlocking tiles up to 120mm in profile. The key thing with this section is this red square again. Hence, the reference in the installation instructions for the window where it was advising that this is the first thing you check before you frame out the roof. Here, we have the size of the window that this is designed to work to, so again, as mentioned previously, ensure this code matches what you've seen on your window carton. And finally, the useful piece of information you will find here is the QR code and if you were to scan this code on the flashing box prior to installation, it gives you approximately a five and a half minute installation animation, taking you from everything beginning with the installation of the brackets up to installing the final tiles or slate around the window.

Unboxing the flashing kit

So the next thing to do is open up the box and I’ll show you the method for that as well. So as with all of our cartons that we've seen up to now, this is our common theme. No requirements for any form of knives to open our box because we have a similar tab system to that used on the BDX insulation and under felt collar box. So again, we're just going to pop this tab up and we're going to pull this across to open the window box, and then we're going to take the bottom tab and pull that. Now, we sort of open up this small section here to give you clear access and then I’m going to come around to the other side, where we're then going to open up either side so you can clearly see the contents of the flashing kit

Installing the bottom flashing parts

So you'll see from the flashing instructions that all of the parts that we're about to fit are numbered one to seven. And on the back of each piece, you'll find a corresponding number clearly stamped for ease of identification. So as the apron is the first piece to go on, naturally, it's number one. So we just flip this around and it's just going to sit neatly against the frame of the window itself.

Now, from here, because we have a profiled tile, what we need to do with the apron is to dress the flexible apron into the shape of the tile itself. So just using the heel of your hand, just gently push everything into the shape of the tile. Obviously, if you had a flat interlocking tile, you're not going to have to worry about this step. Now, once that's done, this next step you would have to consider for a flat interlocking tile. It's the chance to invert the apron ever so slightly so it's going to draw it closer into the face of the tile, making it a lot easier to close off any slight gaps beneath the apron. So to do that, simply lift the apron up. Use the tiles that are there as a little resting point, hold onto the aluminium and just bring it back to you ever so slightly. It doesn't need to be a huge angle, just enough that we have now just changed the approach so that as you can see, it's sort of now rubbing quite clearly along the face of the tiles. This will then be closed off more completely at the end with a soft rubber mallet being dressed across that edge there. So with this in place now, we need to get our second piece which is going to overlap and allow it to be secured in place.

So here we have part number two. So part two is just going to be clipped over this bottom flashing piece, so we're able to use one screw to fix through two different parts. These little nodules here are going to plug into the holes on the window and they give you a temporary fixing prior to being secured completely in place with the screws. So this now means this will hold itself in place and free up a hand for you to go and grab the bag of screws without fear of the flashing disappearing off of the roof. So inside the flashing box, you'll now see a multiple bag here. On one side, we have our installation screws and on the other side we have the little tabs for clipping down the side flashings which I’ll show you a little later on. But for now, we're just going to separate the bags, pop these clips to one side and just concentrate on the bag of screws. So one thing you will find when you open a bag of screws supplied with any VELUX product, you will invariably have one spare screw left. That's just to cover any unfortunate mishaps, if they should occur. So now we get our drill and we start to fix the flashings in place.

So the first screw is going to go into this large bracket on the side. It's important that we don't forget to screw these because one of our side covers later on is going to clip into here, and if this bracket isn't secured, neither will be the side cover. We then work our way along the width of the window, fixing into the holes as we go. Being careful again of the fact that because this is aluminium, we don't want to over-tighten where we may end up puncturing and wearing through the aluminium. And finally, the last bracket secured. So with this secured, we're now ready to install the side flashings.

Installing the side flashings

So here, we have part number three for the side of the window. This part you'll see, has foam running along here which stops short at one end. The section where the foam stops short should be at the top of the window because our final piece of flashing is going to overlap here. So this will tell you which should go on the right and the left hand side. So as we position it with this gap at the top, we have this little section here that’s going to overlap that ridge and then as we push this down, our side piece is going to tuck underneath that fold, so we then slide through this overlap until we hit this double ridge here and the foam comes into contact.

So to initially secure the base, we'll fold this tab over and just fold that around like so. So to secure the side, we're going to use these tabs which will be held in place with these small tacks. And they are going to hook over the ridge that runs up the side of the flashing. So take the tab so that this bend hooks over the ridge and then push that down like so. The tack goes into the hole, and then we just secure that in. Then carry on the process along the length of the flashings as well. So now we've secured this side, we're going to do the same on the other. Now, before we can fit our next piece which will effectively cover the side of the window and cover over our side flashings, we need to remove these cladding pieces here. That makes it a lot easier to fit the parts first and then reattach these after. So to remove these, there is a simple little light grey tab inside which is basically just a little push button. So you will push that bottom in, lift the bottom away and slide that away from the window. Place that somewhere secure and do the same on the opposite side. We are now ready to fit side cover part number four.

As you can see here, I have removed it from the protective polythene packaging, so you can clearly see the number and one other reference point is if I turn this over, you'll see a light grey tab. This light grey tab is basically going to be at the top of the window. So again, this enables you to determine which side goes on the right and which side goes on the left. So this piece is going to go on our left hand side, so we slide it into position and then to attach, we're going to catch these two lips here and they are going to attach into the folds on the aluminium. So we line this up, ensuring that this little ridge here can pass underneath that top cover and as we slide up, we just make sure that we apply pressure in towards the window as we apply pressure up. That way, we'll catch both sections of the bracket in one go and the rubber gasket then overlaps. So part number five slots underneath that clip which lines our clip at the bottom into the hinge, and when you push down, you'll hear a big plunk, telling you everything is clipped in place. And repeat the process on the other side of the window.

Installing the top flashings

The next piece to fit is commonly known as part number six, the hood section. However, as we have a top hung window, you can see from the box it's actually labelled as 6.1 and 6.2 because these come as two individual pieces that we're going to combine together and attach to the window frame, thereby allowing one section to move with the top hung window in operation. To open this up, it’s the same principle as before where we have the two tab systems here. So we just peel back that first tab, pull that along... And then with the second tab, do the same. Then we can open up the box and you'll see the two sections as we mentioned are actually in two individual parts.

So 6.2 as we mentioned, is the initial base part of the frame. So that sits onto the window and just slides underneath our part number five. What we need to do at this stage is only temporarily fix the screw in, because we need to give ourselves a little bit of play here for attaching 6.2. So when you pop the screw in, just take it far enough in so that is has a bite, and that will be ample. Do the same on the other side. So then we take 6.2 and what we're going to do is engage this ridge here underneath a ridge that runs inside here. This is why we need that little bit of elevation on this base plate because what we're going to do is slide this into this channel here. So taking our 6.2, tilt 6.1 up a fraction so we can then give ourselves that little bit of working space and then as we lower that down, we just drop that into place on both sides and we're ready to now secure through the sides here as well as tighten our initial screws. So this screw is going to go in at an angle, like so. And once that's caught, we'll then tighten the first screw. So with this screw tightened, we're now going to do the same on this side.

So the final piece of flashing is part number seven. This is just going to clip around the head of the window using this overlap of aluminium and then a small tab is going to slot through here which will allow us to lock it in place. So lift the flashing to the top of the window and again, something I find an easier way to fit the flashing is to actually bring it in at an angle like so. This makes it a little easier to line this tab in through the slot on the first attempt and once you have that lined up on both sides, you just want to push this down and then push each corner down until it hooks over that ridge. Once that's done, we then fold the tab over like so, and just ensure that these parts clip together. If you wish, you could then fit another one of the tabs and nail that to the baton. With part seven now in place, we're ready to start tiling along the sides of the window.

Tiling around the window

So as we begin tiling along this side of the window, it's worth having planned ahead where possible, to try and get your window positioned so we can incorporate a full tile. Again, it's not always going to be possible but where we can, it minimises unnecessary cutting of tiles. So here, because we have managed to land pretty much a full tile, you can see if I just flip this tile over, there is the need to just remove the nib that will be closest to the window because that’s going to be sitting on the flashing itself. The plan is that a perfectly positioned tile will basically just rest against this ridge. The closest your tile can be is 30mm to the window, so if the upward slope took you over that ridge, that's fine as long as it doesn't kick up. The furthest away you can be is 60mm which basically is the inside edge of this foam. So if the foam is visible, you’ve gone too far. With this in position, what we then need to do is trim our foam. We don't want to just cut and fold. We should be trimming it so that we have just enough foam that the tile compresses it a few millimetres and it seals off the underside. So we want the tile to sit as close to this ridge as we can. So to trim the foam, we need to leave more at the bottom than we do at the top because that’s naturally how the tile overlaps. So to begin with, maybe come down about 15mm at the top and then just cut an even run all the way down until we have, I’ve got 10 or 15mm left at the base. So trim it through from both sides. It doesn't need to be neat; it just has to allow the tile to come to rest. You could use scissors but I very much doubt whether most of you carry scissors in your toolbox. So with the foam trimmed, bring the tile in and we just make sure that the foam isn't too high. We'll be happy now to fix this tile into position.

So we'll now fix this tile in. And we'll do the same for the next tile. So we'll bring our second tile in, hook that in place as we did before, mark the foam and cut. Take the tile away, and then trim a little further down. Now, as we did before, we'll start from here and we’ll work our way along. Sit the tile back into position, make sure everything is sitting as it should. Foam is sealed underneath and then we'll fix. And then carry on that process for each of the courses on either side until we get to the top of the window. Once we've finished tiling either side of the window, we're then ready to bring across our tile course at the top. Here, your overhang should be allowing for a minimum clearance of 60mm from the tile to the window and a maximum of 150mm. The key part of this section is the tile support that you can see here. Don't throw this away because this is the important section that the tiles will rest on as they run across the window because they have no other tile beneath them to obviously give them support. So this can be adjusted to suit the volume of overhang that you're going to need to suit the rest of your tile coursing. Rest the tile on there and once you've put the cut row in, carry on with the rest of the roof as normal.

Once all of the tiling is finished, we're finally ready to put the opening sash back inside the frame. So we're now ready for the final part of the installation and that’s to fit the sash in to make everything weather tight.

Reinstalling the sash and engaging the springs

So as before, if you're right handed, use your left hand to grip roughly around, central above the hinge; right hand underneath to take the weight. Obviously, vice versa if you're left handed. As we feed this through sideways, just be careful of the fact that you have a little less space to work through because we have added the remainder of the cover parts and flashings. Once we have everything back in, use the barrel bolt again to just give you that little bit of peace of mind and stability. Now with my free hand again, I’m going to line this hinge into the mouth of the frame hinge, a little lift and that drops into place. Then on the other side, just move that one around, push it out a fraction, line the two hinges up and a little lift and that one drops in as well. Now I can undo the barrel bolt, let the window come back around. We'll hear the two clicks and everything is now securely in place and we can close the window up.

Finally, as this is a top hung window, we now need to push the sash completely open from the bottom handle to engage the spring mechanism. As you pull it to its full extent, you'll then start to hear two large clicks which will be the springs engaging. At this stage, I can let go of the window and it's free to operate in its normal top hung function.

Adjusting the springs of the window to suit your roof pitch

Once you've engaged the springs and the window is operating on its top hung function, one other thing you may need to do is to make small adjustments to the spring tensions on either side to suit the roof pitch. The plate is positioned to suit the upper range of natural roof pitches for this window, so anything from 45-55 degrees, you won't have to worry. But if it's less, you will have to make an adjustment and there is a small plate on either side, just inside this channel which you can access yourself onsite but for the purpose of the film, to make it a little easier to see, I’m going to remove this inside frame cover so it will be a lot more clear to spot what we're doing. So what you can see here with the internal finish removed are the different settings for the tensioners on the spring system that runs inside the window. This tab here is the one that you would move lower down to suit lower roof pitches. So for instance, if you had a 15 degree pitch, the tab would be in the very lowest element.

So what I’ll do now is I’ll move the tab to the lowest pitch and just show you how the window reacts when the spring tension isn't correct. So just inside this tab you'll see a very small slot. With a slotted screwdriver, you would want to just get into that corner and just elevate that up. With your fingers, you can then slide that down and drop that into whatever position would be required. I'm going to do the same on this side, so obviously the springs both have the same tension. So having moved this plate to the lowest section on both sides, so for a 15 degree pitch, I’m going to now start to close the window and you'll see that because our roof pitch is 45 degrees, the spring tension is going to affect the ability for the window to stay in any given position from 1 degree to 45 degrees, which is what it's meant to do. So as I lower the window, initially everything seems okay. As we get towards the bottom and I’ve almost closed the window, the spring tension is now greater than it should be and the window decides to open by itself. That's a sign of the tension not being correct. So a simple rule of thumb is if the window lifts upwards, you need to move the adjustment plate up. If the window creeps down, then you need to move the tension plate down. It's not an exact science in that you can't just say it needs to be in position number three for 22 degrees, so you may find that you just have to move it a couple of slots down, try it out; if it moves, move the plate accordingly. Likewise, you may get the tension right and then fit a blind at a later date and just the added weight of the blind can cause the window to start to drop so you would have to change the tension slightly. I'm now just going to pop the tension plate back into its correct position and show you again how the window should operate in its normal function.

So with everything adjusted, as we now close the window, we can see it's holding firm. It's worth bearing in mind that when the springs are brand new and just out of the factory, they can take up to three months of use just to bed in and slacken off a little bit. So if you do find as you get towards the bottom, that the window still opens up slightly, just leave that and operate for a number of times and you'll find it starts to settle back in a little bit and it will almost bed itself in. But as you can see, everything is fine and this is what we would expect from the operation of the window.

How to disengage the springs on a top-hung Velux

One last thing I want to show you, which we referred to right at the beginning is how to disengage the spring mechanism just in case you have either accidentally engaged the springs right at the beginning and we want to drop these arms to get the sash inside, or if you're ever doing any maintenance work and you have to remove the glazing unit or the sash itself.

So if you need to disengage the spring, your key focal point is this large, fixed plate just above the adjustment plate we mentioned earlier. What you want to do is take a slotted screwdriver, or similar, and we're going to come in at an angle and rest just on top of that plate. So as you can see, by coming in at an angle, this screwdriver is going to rest underneath a small return on the metal frame, so it's now meeting a little bit of resistance. As I pull down on this end, it's going to lever this section up which will separate the two sections, so before you do that, make sure you've got hold of the window to support it because you are now disengaging the springs. So as I push down, you should hear a bit of a clunk as the springs separate. And you can just see that nodule in the corner there, just where my little finger is pointing which is what sort of engages into the fixed element to make the springs lock together. So taking the weight of the window again, we swap over to this side, slide our screwdriver under here, and again, as before, just lever down and you will suddenly feel the whole weight of the window on your arm. As I lower this down, I’ll let go of the window and you will see what I mean where the spring isn't engaged. It's a dead weight. So once you’ve finished your work, to re-engage the spring, as you did before, simply push the window open until you hear the springs click. And now everything is back as we expected.

So that's something you should hopefully not have to do unless you either need maintenance work carried out on the window or you have unfortunately made a mistake in the early part of the process and you have pushed the window wide open when you were removing the sash. So fingers crossed, you will never need to worry about this.