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How to install a Velux Centre-Pivot Roof Window - Part 4

Installing the flashing kit and finishing the installation

In this 4 part guide, Mark Dymond – Velux Technician installs a Velux GGU Centre Pivot Roof Window onto an Interlocking Tile Roof. Demonstrating the installation of the BDX Insulation Collar and EDW Flashing Kit for Redland 49 Tiles.

In Part 4, we show the full installation of the EDW Profile Tile Flashing Kit, this kit works perfectly with the Redland 49 tile and provides a watertight seal for the Roof Window.

View the other parts here:

Part 1: Unboxing the window and preparing it for installation
Part 2: Fitting the Insulation Collar and checking the Frame is square and level
Part 3: Underfelt collar and Transverse Drainage Gutter Installation

Video Transcription

Unboxing the flashing kit

As with our window cartons, you can see on the flashing carton here, the layout is very similar. Our first line refers to the fact that this is a flashing for a single window into plain tiles. Note, we have the red square confirming that this is for the standard installation height. But again, the code is represented here with a graphic showing that it's using individual soakers for small, plain tiles with a maximum double thickness of 28mm where the tiles overlap. In the midline, we have again the reference to the window size so that should tie up with our window size carton and obviously, the insulation collar that we've just fitted. The bottom code again, just confirms that it's a standard dark grey finish for a single installation. Here, we can see the installation pitch for this style of flashing. Note the minimum pitch is 25 degrees but can be used right up to 90. And finally, our QR code here. If you scan this one, this will give you a full five plus minutes of installation animation which takes you through everything from installing the brackets on the window right up to fitting the last tile around the flashing.

So as with all of our cartons, there is no need to cut the box open with a knife or anything similar. We have these little tabs here that we can just use to pull across and easily open the box. Grab the second one, pull to the bottom and then open up this small section of the box, and then go around to the other side where we can then fully open the flashing box.

Installing the bottom part of the flashing kit

So before we can go ahead and fit the bottom apron, the apron design is slightly different to that used on the interlocking tile. So we need to nail small, little tabs to the window so we can initially hook the apron in place before we fit part number two.

So you'll find this little bag inside the flashing box and we'll just simply rip the bag open and inside you'll find a few tabs and nails that will allow you to nail them into the bottom of the frame. So what you want to do is you can just see two little notches cut along the top here. That's the part that’s going to fold over. So as we nail this on, you want those notches to sit just a little above this flat section of the bottom frame. That way it's got enough height to fold over. So position the tack, get your hammer and we'll just knock that into the frame. And then we'll do the same on the opposite side. With these tacked in place, we can now fit the bottom apron and then hold that temporarily in place before we cover over. Now, with each of the flashing parts that we're going to fit, you'll find a number stamped on the inside which will match with the corresponding illustration in the flashing instructions and on the front page of the instructions. So everything we're going to fit basically goes on from one to seven, with the apron being the first part, hence number one. So we'll flip this around. Line it up against the window and again, you want to make sure that this ridge is flush. It's fine if it's a fraction under but you don't really want it protruding too high, otherwise you might have to make a little adjustment at the side to get it to sit low enough. But with that in place, we can now fold the tab over on both sides, and that will now hold the apron temporarily in place as we go to get our second part.

So the apron is now going to be held in place with part number two. Part number two has a couple of small nodules on the rubber end pieces which are going to slot into a hole in the frame and enable that to sit securely while you then free up another hand to grab the screws and your gun. So line that over and just plug these into the end of the window. Everything now sits nice and securely, and I can start grabbing my screws. So the bag of screws are provided with the flashings and notice they are the same colour grey as the externals, so again, everything blends in. You should always find once you've finished installing or opening each bag, there should generally be one spare screw left just in case you accidentally lose one down the roof. So we're going to start on this side and we're going to screw this end bracket in place. It's important that these are fixed in place because our side frame covers are going to clip into the bottom of this. With that secure, we'll just work our way along the aluminium, bearing in mind not to over-tighten in case the screw ends up driving right the way through the aluminium. So just tight enough that it cushions into the window. And the final screw in the end. So with this in place, we can then start flashing the sides of the windows and this is where again, because of the style of tile, it will be done with individual side soakers.

So one thing to point out is obviously, for the purpose of this video using the training rig, we have only installed a single course of tiles beneath the apron and as a result of there being no eaves course, we have a slight gap underneath here.

If we had the eaves course, as you will in reality, obviously that tile will be sitting at a more reasonable angle and this apron would sit tight to the tile.

Installing the side soakers

Inside the flashing box, you'll see this large box section here, in which you'll find all of the individual soakers that you need to go up each side. By design, you'll see they are actually left and right handed, so if I take one of these out, you'll see that where you see this notch at the top and also if I turn that around, you can see how it angles away from this end to this end; that’s telling us that these soakers are the ones for the right hand side from inside, or obviously left hand side if you're doing this from on the roof. So all of the soakers down this side will be getting used on this side of the window and all of these soakers are on this side. So our first tile that we're going to fit, you'll find that you will have to take the nibs off the inside face because it's going to sit on the return of the apron which basically becomes our first soaker. So if I pop that round, and the important thing is to keep a gap here of at least 25mm. So rather than measuring it, what you could simply do is just pop the first soaker in as a guide, and that gives you your spacing. If we go too tight, you're going to have issues where you’re going to try and force these soakers in and they'll sit at the wrong angle. So with that in place, we know we're now safe to secure that first tile. Then I’ll remove the soaker and explain a little bit further. One thing to note when using the soaker system is unlike our standard interlocking tile flashing where you have a single piece that runs the length of the window, on those types of flashings, you should not puncture through the flashing.

When using the soaker system, it's acceptable because you’re going to cover over that fixing with the next soaker. So I can safely pop a fixing straight through here. So with our first tile fixed in place, the remainder of the window is going to be clad with individual soakers. So to begin with, you'll see we have a single soaker for each side, numbered 3.1. Whilst the remainders will have 3.2 shown on them. And it's important that you pick 3.1 out first because if I flip these over, you'll see the main difference is the angular distribution underneath. 3.1 is quite level whereas 3.2 is then a lot more angular to reflect how the tiles will overlap and interlock with each other. So without 3.1, you would find you have an awful gap here where the soakers aren't going to actually knit together properly. So think of 3.1 as just an intermediate soaker. And we just slot the first soaker so it just tucks inside this metal bracket here, and slide that down until it just catches the inside edge. When we then introduce our first tile, you'll see that we have got sufficient cover here and we just want to position that tile again so that we can just see this channel running down the side.

So that little lip is your guide to make sure the tiles are all positioned correctly. So you'll see for the purpose of the video, we're not going to fully tile along each side of the window. We're just going to put a tile and a half, followed by two singles so it's sufficient enough for you to see how the soakers interact with the tiles. I'm sure you'll be able to fill in the rest for yourself onsite. So if we take our next tile and a half along with our soaker, we can position the two of them together, so we already have that line and we also have it so that the soaker just rests towards the bottom of the tile. Then we can drop that into position like so. You'll notice we've got these tabs sticking up. These tabs can then just be bent over to hook the soakers together to stop anything sliding off the roof as we're fixing the tiles in place. Once I’ve secured this one, we'll carry on along the rest of the length of the window and then come back to us as we get ready for the side flashings. Having completed the installation of the side soakers, you can see at the top what we've got here is not an uncommon occurrence.
Depending on the length of the window in relationship to the gauge, you may find that your final soaker protrudes beyond the top of the window. The simplest way of removing this, because we need to remove this, otherwise our top flashing will get in the way, is to just snip tight to the top of the window and simply bend over the soaker. The main thing is to remove it as an obstacle from the top flashing. So snip, fold that out of the way and there we have a free run for the flashing to run around the side. But before we get there, we obviously have to now insert the remaining parts leading up to part number seven. So we're next going to fit the side frame cover which is number four.

Installing the remainder of the side flashing

Before we fit the side frame covers, we need to remove these parts here which are part number five. You may be tempted to try and slide the part four underneath but it's not advisable because if you get it wrong, you'll scratch the paint off which leaves it exposed to water ingress and rusting over time. So to remove part number five, you'll find a small grey push button just above the hinge. Simply push this little button in. It releases the base of part five. Slide it down from the release part here and store it inside safely to be clipped back on in a minute. Do the same on this side. Pop the button in, lift the base up and slide down and store away. The side frame cover is labelled up as part number four. So you will see two of these: one for the left and one for the right. The way you'll know which side is which is to basically look for this light grey tab which is effectively the top of the window. So this is telling us that this is the one for this side of the window. So we bring this round, rest it on the window initially and just let it slide up the frame until it comes just underneath this block. Then at the base, as the bracket comes into contact with this main point here, we're going to pull the base of the side frame cover in as you push up and that then catches both sides of the bracket in one go. Now, we pop part number five over the top to hold it into place.

Bear in mind, to make sure we get the right side for our part number five, so you're looking for this little checkout to be on the right hand side for the right hand side of the window. Likewise, this little extra lip should always be towards the window as it's going to cover over the glazing screws. So that slides underneath that section at the top which should then line the grey tab back up to the hole in the bracket, and as you push down, that clunk tells you it's securely engaged. And then we'll do the same on the other side.

Installing the top flashing part

So our next piece to fit is the part, if you remember, that came with the window. This is the part that contains number six, which is the section that runs along the head of the window. So all being well, you haven’t thrown this away in error. What we need to do to get into this is again, follow the same rip tab system that we have on several of our other cartons. So we're just going to pop that open and rip that across. And then the same on this side. Now when we open this section up, you'll see the top hood section complete with a little bag of screws to help secure this in place. This is now going to rest across the head of the window, so it just rests inside these little notches and the screw holes will line up to the pilot holes that are drilled into the frame. Open our bag of screws up. So I’ll secure these into place, so take the first screw, place it into the hole there and just tighten that. And then the same on the opposite side. We are now ready for the final piece of flashing.

So the final flashing is part number seven. And this is going to slot over the top like so, just making sure that we get this tab through that slot there. Same on both sides and then just push this down so it hooks over the top flashing. Once in place, fold this tab over and you'll see then how the soaker sits on top of the tile. We'll then simply just place the tile over the top and then using our tile support here, carry the tiles along the top. You should note that your course of tiles here should be no closer than 60mm to the top and no further than 100mm away from the top of the window.

Completing the installation

So finally, reinstall the sash, following the same principles as earlier, just being a little more careful of the fact that we have slightly less space because of all of the cladding parts that we have added. So bring it back round carefully, lower it in, keeping it upright and lock that barrel bolt in. Now, with our free hand, guide that hinge into the mouth of the frame hinge and a little lift and that one goes in. Over to the opposite side, same as before, push out, guide into the mouth of the hinge, a little lift and that one is in. Undo the barrel bolt, let the window come back to you; you will hear the buttons pop out and then close the window up.

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