ruggers

Hi Nick, when you say multiple runs of 60mm tape, do you mean all 4 sides of the window in one continuous swoop, then another over lapping the tape each time until you reach the desired width?. Or do you go 360 on the inside window edge and then 360 on the closer outer edge nearest to the room side? First option wod use a lot of tape. I got the flexi adhesive parge coat on yesterday, just scraped it hard to the block and it went on nicely. Was the thank me later to this aimed at longevity or ease of spread compared to sand and cement? I'm considering doing the inner walls the same now with multifinish before i spray them with airtight membrane (dont think my shoulder will thank me later), Could be over kill but self builders often aim high. Do you have a preference for tape brands you use or they all much alike?

@Nickfromwales I'll give the flexi adhesive a go this weekend, only needs to be a few mm thick then so should dry quick. Get all the closers cut ready, and fit them with a bit of hybrid polymer and if needed some twist nails. I was looking at some soudal tape 200mm, they do two types. One has a self adhesive window strip side, then a peel off butyl side on the masonry edge. The extra tape is the same, but then the full area between the two strips is also a peel off adhesive strip. Not ure if this will make it easier or harder to apply for a full 4 sided opening in one go. I need a decent upstairs ceiling membrane too. I was asvused to use ampatex db90 with siga fentrim 50/85 (£85 quid is steep) because its prefolded and saves tons of tkme. Do the full upstairs before the stud walls go up so its only the perimeter edge to tape up.

I'll have a look whats delivered tomorrow, theyre all dkfferent. If theres an outer wing too, i can cut it off or it will be hidden between the frame and brick anyways.

What does the 150 - 200 mean? Most of my vertical block reveaals are 1050 to 1275mm high. I've used the brush on around the full house perimeter before i built the masonry hangers into the block work diring construction and its quite an easy product to apply and it does fill a lot of the grainy holes, a parge would give this a better finish but i thought the liquid avcl would have a better lifetime bond to the blocks rather than adhesive then painting over that? The cavity is 150mm, frames set back 25mm. Ill assume the closers wings are 25mm, so there will be 150mm of plastic to cover. I didnt think theres a need to paint over the whole closer. I proposed to tape the inside closer edge to the parged or liquid sealed inner leaf block, then use a folded tape to tape the window frame to the closer 15/50mm or similar. Then adhere my plasterboard to the reveals over everything. If i don't vertically tape the closers edge to the inner block before the windows are fitted, ill be taping over metal window straps too so the tape wont be continuous betwen plastic and masonry, it will be taping over metal too.

I want to ensure the laps/wings of the plastic closer have a good seal to the inner block work and need the closers fit before Tuesday windows. The brush on soudal lq has reinforcement fibres in and is a paste and much thicker than what will be sprayed onto the inside block work later on using their sp version. Its already bought. Passive purple is great but the price was far too expensive.

Hi, I'll reply to you both. Correct me if theres a better order to do this before or after the windows are fitted next week. I was thinking i need to do some upfront work. See picture for my window reveal. Its 100mm dense block inner, 100mm pir set back by the depth of the plastic cavity closer 25mm. 50mm air gap, 100mm facing brick. I'm going to fit the cavity closers this weekend before the windows go in. Im modifying them and adding 50mm thick pir to make them 75mm total, the extra bit wont bridge the cavity, but will overlap the set back window frame. I'm using soundal soudatight brush on around the reveals, the rest of the walls will later be sprayed after chases are completed Cant get anyone to wet plaster so dot and dab boards. I planned to paint the reveals this weekend to seal up pores in the blocks, then add the cavity closers over lapping, then tape closers to blocks, then windows fitted with the straps drilled into the inner block work, and then touch up over the brackets and screws with tape or more membrane. That way any air tight tapes are adhering to painted blockwork and will adhere much better than to bae dusty blockwork. I thought if i fit closers, then windows in, then try to paint over it all and tape closers to blocks it will get messy. It sounds like i need to parge coat the reveals with sand a cement asap, then add soudal liquid membrane paint, then cavity closers, then windows fitted, then tape over? @Nickfromwales

Which airtight tape is best for window reveal cavity closers to blockwork? I need to start buying air tight tape for various areas of the build, but first up, i need to order some asap to seal the plastic cavity closers to the internal block work reveals before the windows get fitted next week. I've just realised I'm going to need to tape one side of the closer before the frames go in. I'm having the frames set back into the cavity by 25mm, so window reveal fixing straps are being used, these will over lap the closer, meaning taping later wont make a decent seal. Siga fentrim was suggested for some areas but its very expensive. Just to add, all block work reveals are painted in airtight paint and closers will be modified to be thicker.

He only specified nails. The hooks are very expensive

No one could get me a price until the new year. Did you use 2.65 or 3.35mm? Cheapest i can get is £89 per 5kg of 2.65mm, which is a lot cheaper than online. Amazon is £82 but not sure what they'll be like.

I'm having a slate roof installed on a self build, 400 centres, and I want to know if copper clout nails should be used or aluminum? The slates are 250 x 500mm 7 to 9mm thick. 38mm clouts required and 30mm for the eaves course. Aluminum 3.35mm or the roofer says if using copper I could use 2.65mm. I want the roof to last 40 yrs+ Some online reading says aluminum may fail between 20 and 30 years is this true? We're 3 miles inland off the West coast, there's a few houses around but we do get a bit of wind in winter.

Yeah its creating a slip plane they say. So many methods people choose from, full mortar bed underneath, others spot bed them. Full length 100mm dpc vs full length stepped dpc. Small cut of dpc over the stooled top or not. Expansion foam between any joints if the cills are in 2 halfs. I'm not sure if this is a good or bad idea because the foam between isnt goijg to compress if theres mortar above in the joint. Some use a hybrid ploymer to fill the gap not mortar. The correct dpc detail and the centre pointing are the details i need to get right. These are being installed tomorrow

These are the cills, just basic stooled.

@Oz07 Thats what I was thinking but I wanted to see what others have done in case I'm missing something. The water cant get into the house because theres an open cavity gap.

As in 125 underneath the cill, up the back of it and then back over the top where the UPVC frame and cill sit over the cast stone? Any idea what the benefit of an external cill tray as opposed to just having 100mm DPC under the stone cill? My rear windows won't have stone cills , they'll be UPVC frame and cills direct onto the brick work with DPC or stepped tray underneath. It just feels like a stepped tray is going to prevent water escaping since theres no weep vents on a cill course where as a window lintel has weep vents every 450 horizontally.

The cast stone company won't provide details, they just produce them only and leave it up to the builders. I discussed two methods of installing cills I seen regularly and they said everyone has their own preference. This is what makes me unsure about the stepped DPC, because any water finding its way in from the outside into the cavity won't have anywhere to go, so it will just remain damp against the plastic tray. Why is a stepped tray needed when below the cill is open cavity, or a window head with cavity tray and weep vents? I have some expansion foam left from the brickwork, looks around 8 to 10mm thick but its knowing how far to set it down between the centre joint with them being in 2 parts and colour matching mortar pointed between them. I didn't know there was another option other than just using 85mm stub cill with a 70mm frame, The stone cill raised section is 40mm to bed the upvc cill onto with the frames fixed using window straps.