Mansard loft conversions are the most technically complex type of loft conversion in the UK, requiring precise engineering solutions such as steel frame construction, proper water drainage systems with furring strips, and structural calculations for rafters and hip rafters at specific angles (typically 45° for hips and 30-40° for roof pitches). The construction process involves multiple stages including roof stripping, rafter installation, waterproofing with OSB and membrane, brickwork with cavity trays for moisture control, and window installation, all while managing challenges like weather conditions, material supply delays, and complex geometric calculations.
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WE REMOVED THE ROOF OF THIS HOUSE EVEN THOUGH RAIN WAS EXPECTEDAdded:
Loft conversions in the UK are really, really common. This loft conversion is the most technical and difficult of all of them.
>> Boggle your mind at times. Hang on. This isn't the right one.
>> This family chose a mansard conversion because it maximizes all of the space available of the footprint of the house.
And here's what happened previously.
Someone forgot to turn the cameras on.
So, the steel frames up and we've got no footage of it. This steel frame holds the timber structure which forms the roof and walls. This is the complicated bit of the roof.
>> So, we've built them. We've started on the flooring >> and get this in some sort of the dry.
>> We've constructed the flat roof across the steel frame and built the dorma out the back.
>> That was quite a big section where there was a lot going on.
>> We've designed and built the opening for this huge window which is going to sit in there later. 1.8 a really big window and alley. And now it's time to crack on.
>> Bit of an issue with the window. The mechanism doesn't work >> with all of the tasks that are left.
Might be some changes needed to make this awesome.
>> So, we're doing ference strips, people.
You can't see it from here, but we're going to have a little bit of a fall in this flat room.
>> No, that way.
>> So, apparently the flat the the fall is going that way.
>> Yeah.
>> Ah, now I know why the why fing strips are so long.
>> Yeah, that's it.
>> They're going that way.
>> I know they drive on the other side of the road in Spain, but I didn't realize that furring strips go the other way.
How it was originally drawn and the reason for Alberto's confusion is the furring strips on the drawings are going from the roadside to the garden. Al and James have had a conversation James the architect and they've decided to switch the directions and go left to right across the house. Even though it's a flat roof on top, there is actually a built-in incline in the directions in order to control the amount of water that hits the flat roof part of it. This is going to push the water very slowly towards the drain where we can control it down into the road wastewater system.
But it didn't exactly go to plan. Love fitting everything twice. What was wrong with the previous?
>> I marked up. I started from the thick bit in the middle and put the thick bit in the middle and then turned up and went broke. I need the thin bit on the outside, not the thick bit in the middle.
>> Bro, what are you talking about, man?
>> Let me draw your picture. These are called fairing strips. And the fairing strips have a thin end and a thick end in front of Scotty. I started with the thick end in the middle and then was going to cut it here, which was going to be about 30 mil off the steel. Al needs it to be almost zero at the steel and then whatever it is in the middle. So now we got to do it all again. But it's all right. Everyone makes mistakes.
Even Donna does.
>> There was that one time.
>> Nice closeup of me breaking my knees up here.
This little setback was overcome with all hands on deck to remove the strips.
Once they're off, we left it to Alberto and Scotty to put them down properly.
Maybe I just shouldn't get involved in this stuff. Hello everybody. We got the fairing strips with the right pitch roof always be top and the sides. Hoping to felt all of the OSB, cut out the window holes, get it all felted around, and on the top we're going to tarp it. As the OSB is cut away from the windows, we get a great indication of how the room will appear. Once completed, the views from this room are looking absolutely fabulous.
Here's one for the comment section. In England, what is the best view?
With the holes cut in the windows, it's now time for the boys to continue on building the cheeks of the dorma. Now, you would have seen some of that in the previous episode, but this part that they're building here is right here on the plans. Hopefully, that'll make sense.
>> So, is this like the other side now?
>> Yeah. Yeah. We're going to do this cheek complete mirror image.
>> So, we'll get all this we can get all this boarded and I guess we can wrap all that and you know you got something solid to fix to here. Once it's all done and it's wrapped, you can walk away from it knowing that that's done and protected and then we can carry on.
>> The sheet material going on the outside is called OSB. that becomes a structural part of the wall and keeps everything all rigid. Now, generally the rule is measure twice and cut once. But sometimes your day just doesn't go like that with all these complicated angles.
Sometimes you measure it twice and then you cut it twice. In the end, outcome done. OSB on. Let's go.
>> Bit of a missile.
>> Cut a 40 on one end a minute. That's a 40 as well. Longest to shortest 149.
>> After a little while, the boys get a nice little rhythm going. Measure, cut, nail, place, repeat.
>> 575.
>> How come I'm no one down here running around anyway? pulling the age rank, I >> always seems on these videos like all of a sudden it's just done. It does take hours and hours and hours of work, but suddenly both of these cheeks are complete and the room is starting to take shape. Nice. It's a really good thing it is starting to take shape cuz the weather's changed again. We wrap the sides up with membrane to protect it from the wind and the rain and it's somewhere nice and dry for the boys to go to get out of it. The hammer tacker works great for putting the membrane on except when steel.
>> As the sun sets over this home, well, kind of. As the clouds drift away to the horizon, what we can see is a new shape is definitely starting to look more like what those pretty pictures are. On top of working our brains with all the maths, angles, and calculations that Alan and Scotty have to do, we've got the everchanging spring weather to battle against as we perch precariously up ladders and add to these jack common and hip rafters.
>> Put a double jack rafter in here.
>> It's no time to rest. Axe smacks the spike. The brickies are scheduled to arrive in a couple of days and this isn't ready for them.
Sometimes your calculations work and sometimes they don't. Keep going, Scotty.
Even though we still have demolition to complete, it's important to try and keep the area as clean as possible. There is not a lot of space to actually stand cuz the floor's not quite finished.
Especially when the plumber and electrician are due to start their first fix.
>> All of this got to be swept. So, I'm on it.
>> No vacuum cleaner.
>> I think there is. I think they're trying to just torch me.
>> You got to work up to that.
>> Just waiting for it to come to make a tornado and they just send it everywhere.
>> Tell you what, they could really do with a hoover.
>> Really good do. It's utility day. So, we have to remove everything.
You can hear the skills going. It's utility day. So this side of the loft, we've laid the floor joists and the triples there. And then the plumber obviously got to come and do a bit of first fix. We tidying up as we go and make him space so he can uh run the pipe.
So that you're not like doing a full squat. So I'll get to here. You see what I'm I get control here and then I don't have to be like bending all the way down as far as lost faces go. Is this kind of fairly standard?
>> Anything?
>> Fairly on suite, little bedroom, little radiator in >> any major challenges that you can think of?
>> No, we haven't had any yet to be first.
Fairly straightforward.
>> Just got to watch that hole below you cuz uh once it goes down, everything's gone.
>> Today we're going to ply all of this and that's it. Once we ply this bit out. We are out cuz it's Easter week. We're going to celebrate the resurrection of Jesus Christ and House of Wine. That's what we're doing today.
>> Death. The death first, isn't it?
>> Yes.
>> Yeah. Sorry. So, we're going to go step by step. First is going to be the death.
So, we're going to be be sad and then we're going to be very happy on Sunday.
>> Why are you putting another piece of wood in? cuz I got to move the pipes. We got it on the plate. So, we know it's safe.
Let's jam it in there. So, you see how this is way way weight way bearing there.
>> Yeah.
>> One, two, three.
That's it.
>> I need your help again, mate. Just to hold this timber up. I need to just do a slightly different bird's mouth on it.
>> 20 mil.
>> Yeah.
It's a really complicated piece to put in.
>> Yeah, they can kind of boggle your mind at times.
>> There's so many different angles.
>> Yeah, this is it.
>> And Henry's finally arrived. He's going to give Lock a hand inside. I guess it's better late than never.
Albert's got this thing about about um doing measurements in centimeters.
So like like 2750. He's like 275. Yeah.
No, no. 2750 like you going to say it to someone. They're going to come back with a 275 mil bit and go. There you go. What the is that? 2 m and 75 to length and then we'll cut it to width at 980. All right.
Hi, my name is Alberto tomorrow and this is Silur.
>> My name is Maximus Desimus Meridius.
>> My name is Enigo Montoya.
>> Welcome to the crunch.
Today we have got a job on. We've got to get this roof stripped. We've got to get all the timber work off. And we've got to get the rafters in, the walls up, hit rafters on, and water tight. We've basically got rain coming in in about 30 hours.
>> Today is sink or swim day. There is a lot of roof there in order to get off and back on again. It's going to be a challenge. Let's go. We got Scotty too hot >> stripping the roofs, mate. Oh, looks almost went down through the scaff.
Me and Scotty are going to start looking at getting the rafters in uh whilst the rest of the boys continue to strip the rest of the roof. You got >> uh in the van.
>> Well, ain't much use there.
>> Damn. Damn it. Damn.
>> I always know when it's 10:00 cuz I can hear Scotty's stomach rumble from across the street. We're getting on well. We've got one corner stripped. So me and Scotty can now start focusing on this hip rafter whilst the boys strip the rest. Got quite a lot of stuff coming out very quickly for a small site. So we got skip being changed in a minute. The boys are just making a pile of different types of material so we can put some in the script and then some will go off to be chopped off.
The boys are still stripping. We got the first rafter cut. We're about to check if it fits.
I love it.
>> Lots of spice time on the camera.
>> Yeah, look at that. Such >> lovely.
>> One hit wonder.
>> The roof is all stripped. We started building the new rafters and working out the wall what the hip's going to sit on.
So, me and Scotty are just going to stud this out and then we're going to move over the other side and then we're ready to start bringing the common rafters all the way through.
>> Oh my god, what's going on here?
>> We got a really big hole in the side of this house. So, but we man we've worked out the rafters. Uh we've got one of the hips in over there.
So, we've just got to basically we've got a pattern. So, now we just got to cut them. This roof is 300 centers because it's only 6x2's but spanning just under 4 m. So, the structure engineer said it works but we've got to put more in. Get this thing buttoned up cuz we may have a little bit of rain coming in a bit later on. What's the Spanish word of the day, mate?
>> Spanish word of the day is >> Spanish word of the day.
>> What's the Spanish word of the day? The Spanish word of the day is sintto.
When we say somebody is a sino, it's a homeless person. These people are not homeless, but they definitely don't have a tro. Look at them. Tu is gone.
>> That's how we go.
>> We still got a hole in the roof. We had to get some extra timber cuz I didn't calculate for the fact there were 300 mil centers. Whoops.
Really hot out here. Sun's out, guns out. We are now going to start water tight. So, boys are going to do the cheeks and then they're going to start doing this dorma whilst I continue to bring the rest of the timber through. We got a little bit of rain coming in tonight.
We're just putting it up now. We still got one little corner to build tomorrow and we got to do a few doubles for some vexes.
>> So, we're going to get it buttoned up.
5:00.
Everything is buttoned up and all of the timbers are in. Pretty much one roof off, new roof on one day.
Well done, guys. Smashed it.
Something's bothering Big Al. He's looking at this hip going, "What's not going on here?" Here's some suspenseful music to watch Al create himself a hip rafter.
>> Quite unusual shapes.
>> No, every hip's got one of them on it.
Every hip's a 45° angle and then basically you've got whatever pitch uh in this instance it's a 30° that way, 40° that way, and then it meets the two rafters that come up and that forms a hip.
>> And that one, >> hang on. This is the right one.
>> This looks pretty much right to me that way. This one is square level. Sweet. Try that.
>> Some things in life are sent to test us.
For Al and Pablo, this seems to be one of those times.
>> I think it needs to go a lot shorter.
Yeah.
>> So, we have a gap here for the RSB to slot up. Try that.
>> Boom. Shack it up.
So, what's going on here, Scotty? Uh, I'm going to mark the 400 centers off here onto there, >> and then we can gauge it then. Because we felted everything, it seems we don't want to really want to rip it all off.
So, this is better off to do it from the inside.
>> So, if you get a piece cut a 40° >> with a 45 back cut.
>> Yeah. Yeah. So, we get that cut and then then we can measure from the short bit to the to the plum cut and then we measure this depth here and then you know then don't.
>> See you later. Bye, Callum.
Just like Deliveroo or another unnamed food delivery service, pizza arrive with a fresh supply to Build the bridge. Build the bridge quick. And that is how the woman conquer your city.
We're back into it. Heading rafters to the house front and preparing for the two new V-lux windows to go in.
>> Fully threaded screws, people. Fully threaded screws. This This should be a law. You shouldn't be allowed to have a screw without full thread all the way.
>> Gentle does it.
>> So, you got to move two of them over for the bellies.
>> We obviously had to waterproof this yesterday. We're going to make some doubles so that we can put the vexes on.
>> What Pablo's talking about here is the side of the vex windows need to have extra timbers put in in order to make up for the bit that's missing in the middle.
So, we're going to double up on both sides and then put double trimmers across the top and bottom of the V-lux windows. While Pablo removes the offending rafters that no longer need to be part of the building.
>> Relocation. Relocation Devon style.
>> Al does some maths.
>> Which way do you want to move this?
>> That way. Over to that. Yeah. You good?
>> I'm good.
>> We need the Veluxes to be in exactly the right place from the inside. So, he's trying to work it all out from the outside till they look perfect from the inside.
>> Cut that out.
>> Look, Tyson Fury on site, mate.
Wrestling the felt.
>> Where's your next fight?
>> Cheek pied.
um the other hip in. We've got all the hip rafters in the other side. There was a couple little bits that needed finishing. Got all of this lot cut back ready and got all the double trimmers in for the vellock. So, not a good day inside tomorrow, boys. Isn't it?
>> Yeah. Well, you watch your son will be out.
>> Hi to everybody from the silver friend sphere. We are back. What's happening today then page? Today we are going to start and I mean start because it's going to be long to lay floor joists in this mansion inside the castle of dreams.
A little lovely blue sky today. Um as you can see it's a bit of a mess in here. Those are with those windows that we were framing out. Bathroom.
Oh. Oh. Oh. This way. Bathroom.
Bathroom. Shorter 8 in joist for the area of where the steps are going and longer joists for the bedroom. Me and Scotty Oh, wrong ladder. Me and Scotty have just marked out all of these rafters to be cut back ready for the backboard to the fascia. So, we trim them back, get the backboard on, level it up, and it's ready for the faces.
What's the matter with this picture?
>> What do you mean?
>> I'm holding on to the pin. I'm cutting a >> Is that the most efficient tool there is >> for these sort of angles? Yeah, cuz it's coming out. No, when the straight ones, you just use your electric saw, you know? Yeah, >> cuz they're easy when they're on an angle like that is >> setting it and trying to do it that way.
It's not really going to help.
>> While Scotty cuts back the rafters on one side of the house, on the other side, Jacob is putting down the DPC in order to create the cavity tray on top of the wall. This is going to make sure that if any moisture gets soaked in through the bricks of our new gable, which isn't even there yet, it's going to slide down the bricks. is going to hit this plastic sheet and then it's going to go out through the wheat vents, meaning the inside of the house stays nice and dry.
>> These ones are to give us a bit more height where the joists are sitting on these plates. Basically, we need a bit more height there so that the floor joists are going to be the same height all the way through. Oh my goodness. Now that both cheeks have been boarded and we're ready for the brickies to arrive, we still need quick, easy access to the loft area. However, when you are 6'6, that becomes a bit of a challenge.
>> All right, it was a good day, wasn't it, Pudge?
>> Oh, it was lovely, mate.
>> We love your pads roll.
>> We love you.
>> Thank you, darling.
>> Thank you, honey.
>> What have we done today then? P.
>> Nothing.
>> The strike, isn't it? Strike day. Strike day. Yeah, I've certain all of this and then me and Scott here made all the cuts ready for all of them to be back and put the backboard on. Jobs are good in. So now we're off for 4 days. With the Silver Fern team on break for Easter, it's time for us to give a little bit of thanks. This thanks goes to all of the people that help us create all of these amazing spaces. We all come from different backgrounds, different lives, different cultures, different continents. Without this team, we are unable to make what we make and broadcast it to the world for you guys to see. There is however one person that you guys haven't met. He's the posh one.
This is James and he is the architect who has designed this amazing project and we're just going to have a quick chat with him about some of the challenges, some of the outcomes.
Don't leave me down, bro. I'll try my best. Cool.
This house sits on a street where all of the roof ridges go in one direction except for this house which goes perpendicular. That roof ridge goes from the front of the house to the back. And when you're building a dormer extension, you ideally want the ridge to be going facing the garden. Therefore, what we've had to do here is rebuild the roof, turn the ridge around 90° to facilitate lots of space upstairs with views across the city and plenty of room for the master bedroom and the on suite.
Essentially, the space that created upstairs was what the client was seeking fairly early on. So there were only a couple of iterations of the floor plan, but once that's in place, refining the appearance of the dorma, refining its proportions took a few iterations that go from the high level exercise at a sketch design exercise like this to the planning drawings to then technical drawings with the building regulations where with the client we establish exactly how wide the gaps are between certain rooms, how generous the staircase needs to be. So it continued in different levels of refinement over the course of 3 to 4 months.
We changed it from a masonry construction upstairs. But as a result of our collaboration, we decided to build that upstairs gable wall in timber to make your logistics much more straightforward and to save the client money. And what I would add is building in timber frame but with a brick outer skin looks like any regular brick building. It allows us not only to build effectively up high because timber is not as heavy as No, it's not concrete. No, it's not. It also allows us to get much better thermal performance. So, the quality of this dormer is very good in terms of its thermal qualities because we can get insulation into that timber frame, meaning that the energy costs of this house looking forward are going to be much more affordable. Told you it was posh.
Thank you very much for taking the time to talk to us. Let's go back see what the boys been up to back at site. Bye.
So, after a good break off, the sun rises over our Mansard project. Over the next few days, there's going to be quite a transformation, and we're really excited about it. Nice day to be a roofer today, isn't it, Lock?
>> Yeah.
>> Nice day.
>> It's a nice day to be alive.
>> Yes, mate. Love it.
>> Howard and Jordan, the Brickies have arrived and begin loading the scaffold with the bricks. Now, as Al explained in the previous episode, >> there is 750 bricks on each side that we're going to try and store up here. We can't put them on this scaffing because this scaffolding is a complete bridge.
So, there's no poles going down on this scaffolding at all. All the bricks will be stacked on each end. And then we have two laborers that will just be feeding the brickies as they need them. There's going to be a bit of a game to get this right. And we don't want the scaffold to come crashing down.
This little contraption is called a bumper. It loads bricks up scaffold really easily. We love it and it makes good footage.
750 bricks aside in no time whatsoever.
And there's no risk of the boys falling down the ladder. With the bricks loaded out on the scaff, it doesn't take long for the boys to start getting these bricks in the building, which is amazing. However, we can only get to a certain height before we need to adjust the scaffold in order to be able to get right up to the top. It's simply too tall.
Oh, it's always a nice moment when the V-uxes start coming up on the other side of the house. how it is set and ready to go. First of all, I'm switching me tools in the mop cuz it's a Friday thing, you know what I mean? And um I got to build that and build these.
I put them there. Build the leg cavity trays in cuz that's an out that's a it'll be an outside wall that then becomes an inside wall. So these leg cavity trays stop any ingress of rain water and shed it out onto the roof.
I get the dubious honor of scrabbling about in there like a mountain goat.
>> So they just go on the edge where it meets that roof.
>> Yeah. Towels that through to there. When it rains, these go down onto leg and then down into that one there. Hang on there. Hang on a minute. Yeah. Go on. If you video that comes out the bottom here. Look.
So, it's coming out the bottom. That's how they work.
>> Yeah. Into there. And then a wedge.
>> Watching Howard is like watching a master craftsman at work. He really does make it look easy. It's not. Thanks, Howard. Thanks, Jordan. Love your work.
>> Al's got a problem. Let's go and find out what it is.
It's >> a little bit of an issue in the window.
The mechanism doesn't work on one of the vellers, which has come straight out the box. Bit annoying though cuz we've obviously carried it all the way up here, unpacked it, put the buckets on, >> put it in the hole, and uh just to take it out again and take it back down.
>> Is it going to be a bit of a setback or be a quick swap over?
>> Yeah, I'm not sure. I'll give him a call and see what the crack is.
Good morning. One of the Bellers that I picked up the other day has got a bit of an issue with the opening mechanism.
Have you got any more in stock? It's um it's an 1180 by 780. Right. So, it doesn't look like they've got one of the windows in stock. Um, so it's probably a 3 to 4 day lead time, which is a bit annoying cuz we were hoping to get that in um over the next couple of days. We may just have to wait on that one.
With the first V-Lux on its way back to the supplier so we can get that issue sorted, the team move forward with installing the second one.
>> Good system.
>> Oh, we're not a system work. Well, some Spanish lad that were here on Friday promised me we were going to get all the bricks up. I don't know what happened to that.
>> I thought we left at the same time.
>> Oh dear. We'll get them bricks up. We'll get them bricks up. Yeah. Yeah. Going to get all them up for you.
>> What are those pieces for? It looks like you'reing the place. This is the campy side.
This is what ties the brick work to the timber frame.
>> The reason why we tie the bricks to the timber frame is so that we don't end up with a gable blowing out. Now, you would have seen loads of reels on social media when big storms and stuff like that where the gables simply fall out. Our family home was destroyed. So, you'll see behind me right now, one of our friends has plywood up to try and prevent the house from further damage.
But the night of the storm, between 3:00 and 4:00 in the morning, the gable was completely torn off. uh the side of our house.
>> Now the gable is the triangle bit of the house and what we're doing here is putting these special ties in. So we nail it into the timber frame which is attached to the original house. We then need to attach the bricks to the timber frame and it all becomes one structure using these special little ties. So when it comes to choosing bricks, is there like a standard exit brick or do you have to try and color them?
>> These bricks are from Barrowing Furnace up in Cumbria. These these furnace bricks are just flipping excellent bricks. They really are. They're such a good brick company. And they just happen to be the best match for the the extra bricks. Such a flipping good imper in what's it mean when it got impervious.
Is it water? They're 99% bloody waterproof. And they're a real good brick. If you were to try and break one of these with your TR, your fillings would fall out. As a guess 1845. Oh goodness. And a really good Oh, if I get commission off them.
But yeah, they are such a good brick. I'm ask Jordan if he will express how waterproof these bricks are through the medium of dance.
>> They are the best. They >> That's not exaggeration either. I know people think, "Oh, no. It shouldn't be that waterproof. They're only like that waterproof, but they aren't that waterproof.
>> With Howard doing his little disco dance on one side of the scaff, let's jump to the other side of the scaff where it's time for us to start thinking about some slates.
The bumper is a great bit of kit and we love using it. Unfortunately, only the little tiles get a ride. The larger ones have to be carried up the ladder by hand.
What an episode that has been. I hope you've enjoyed it. We really enjoyed making it. Few thank yous. Thank you to the boys and girls at Silver Fern. Love your work. To all of our amazing extended family, our subbies. You guys rock. Thank you so much to our amazing clients. Thank you for letting us do what we do, filming it and broadcasting it to you guys. And most importantly, thank you to you guys at home for watching. Next week, we've got a really exciting episode. There's going to be plumbers, there's going to be sparkies, roofers, brickies. Hopefully that window turns up cuz I'd really like to see that in. Until then, thanks for watching. See you in a bit. Love you. Bye.
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