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Hi All, Just need some advise please, the blockwork for my extension went up back end of last year when we had rain pretty much every day through October, so the blocks got wet. I've now got many cracks in the mortar vertically, some step in places, some go horizontal and some split blocks vertically. Most are hairline, a couple slightly wider about 1mm. They're around every window, and on every wall, in some places only 2-3m apart. The long wall of the house, 13m, has brickwork on the outside skin (blockwork inside) and doesn't have any cracks in the external brickwork but cracks on the internal blockwork. The other walls with blockwork internally and externally have cracks in both skins. No cracks go below damp course, none are wider at the top, they're all pretty consistent. My understanding is the cracks are very likely to be from materials shrinkage which would make sense given the weather when the blockwork was completed. I was hoping to wet plaster the walls and the external blockwork will be rendered. I read thermal movement cracks shouldn't necessarily be filled as can stop the house returning to the original state which then leads to larger cracks over time, though if this is likely shrinkage (thoughts?), I don't believe I'm likely to see any further movement anyway. Would obviously like to avoid having to scrape out the mortar and/or replacing blocks if unnecessary. In summary: * Does this sound like normal shrinkage? * Assuming shrinkage, will plastering straight over the cracks lead to cracking of the plaster in the future? * Would future cracking in the plaster be reduced if the cracked mortar was scraped and filled, the cracked blocks were replaced or silicone simply be run in the cracks? * Would dot and dab be a better plaster solution or do the board joins just crack if the walls move anyway? Thanks in advance for any support!

Hi I am installing an electrical roller garage door. The guide rails will be installed on the inside of the garage so they won't be visible. My issue is that both side of the opening are not Plumb or level. One side you place the guide rail to the bottom brick and it runs out by arround 20mm And the other side is the same but runs out at the bottom I am not sure what would be the best way to attach the rails so they are plum as its quite a big run out. Was thinking of placing a piece of wood the hole height and packing out allowing the rail to be attached to a plumb service Attached some photos Thanks

Hello. 3 years ago we had 2 new upvc bay windows fitted by an established company in the London area. The ground floor window has sealant between the sill and the brickwork, the first floor window does not. We have damp on the first floor interior wall below the window but not on the ground floor wall below its bay window. There are large gaps between the first floor bay window sill and brickwork and 2 packing strips can be seen from street level on both sides of the bay window. (cant get photos to upload to site). I have several questions and will appreciate any thoughts. 1. Am I correct in thinking that this is how water is getting in? 2. Is it normal to seal gaps under a ground floor window sill but not a first floor sill? 3. Should I ask the installers to come back and seal the gaps? Regards DaveAF

Hi looking for advice please landscape building a curved wall with piers outside to go around a patio agreed width is 400mm as it will be used to sit on also with some flat coping stones. my plan was a half-brick skin either side with a 200mm void. could I use brick ties to hang over into the cavity and infill with a dry mix of concrete - is this too much, what would be your advice please also does the wall have to be built into the piers so the bricks overlap into the piers and would I need to use ties or could the piers be freestanding with ties and tie the wall into the piers? thanks In advance

Just getting my head around wall construction and the balance of vapour, heat and draught resistance and how they work together. I'm planning to renovate my walls (internal, as neighbours in the terrace aren't necessarily enthusiastic) house-wide - the solid double-brick victorian design (basically just bricks with plaster on it) has some significant room for improvement. But there are a dizzying array of options and configurations for internal wall insulation and it seems like information "out there" hasn't quite kept up with our developing understanding of water vapour and airtightness. Here's my current understanding, am hoping folks can correct me where I'm wrong (from outside to inside): 1. The air outside: The weather here in the UK is rarely on average over 21C, so the inside of the house will almost always be warmer. So the design needs to address water vapour that is *leaving* the house, getting cold and turning to condensation at some stage during its exit from the inside rooms. Not much reason to worry about water vapour coming in from outside. 2. The outer structural layer, that is in my case a solid double brick layer has a Vapor Resistivity, N s/(kg m) of 45 - 70 (got that from here: from here: https://www.engineeringtoolbox.com/vapour-resistance-d_1807.html). This means that it is "semi-permeable" 2b. Leaving on plaster (or not): Most of my walls have plaster (in some cases lime plaster, but haven't done an exhaustive survey), which I gather is straight-up "permeable". I can't see a consensus as to whether it's better to remove or not remove plaster, but I gather it may be necessary to remove (a) so that one can assess damp problems in case they aren't fully permeating the plaster to the inside layer of the wall (to show on paint etc.) and (b) so as to install some sort of membrane, or (c) obviously to address where there has been damage, and it seems to make more sense to leave it off if it's already off. But it seems like some folks like to save time and energy by leaving it on if there aren't mitigating situations. I'm about 70/30 leaning towards removing paint and plaster to expose the brick and check things out properly. 3. Air gap (or not): I've noticed some disagreement as to whether an air gap is now necessary. I gather an air gap is needed so that air can circulate vapour so that it can evaporate or vent out through the brick wall rather than condensing as it might in a tighter space without air. For the air gap, I can do battens over walls - and it seems that wood and stainless steel are the likely options here, nailed or screwed. Steel is more expensive, but will avoid rotting better than wooden battens (though damp proofing should ensure this isn't happenning!). Seems like Damp Proof Membranes are also an alternative, but a bit of overkill for my purposes here as it's not a cellar and all walls are above ground. But then the 4. PIR boards. I'll get these with foil backing, as this has an astronomical Vapor Resistivity value (4000), putting it on the very high end of "vapor impermeable". But it seems that some folks prefer the more labour intensive but easier-on-battens-long-term "warm battens" approach, where a insulation is split into two layers (a) a membrane is put down with half or more in layer of foil-backed insulation and then (b) an inner layer of battens with more insulation boards inbetween. This keeps warmth around the battens and ensures that moisture will condense further out in the wall. This seems reasonable to me - and I don't mind the more challenging job if there's an efficiency to be gained. What I'm not sure about is whether to use a membrane or foil-backed insulation boards for the vapour membrane at this stage. And if I use a membrane can I skip the air gap? 5. Plasterboard. "semi-permeable" here, skim on some plaster and ready to go. With regards to thermal transfer and insulation performance, here's what I've got: 1. Air = cold 2. Brick wall has u-value of 2 W/m²K or so 3. Air gap will reduce this slightly 4. PIR boards have a very low U value, which is why they'd be preferrable in walls to various wolls, cellulose, or other good options. I'm aiming for 70mm PIR or more (if possible) to try and get as close to or lower than my target U-value of 0.30. 5. Plasterboard adds a bit here too, but not much. Compliments of diydoctor, here's a diagram of what I'm doing: Option 1 (keep plaster, cold battens): Option 2 (warm battens - ignore blocks in picture): Option 3 (with service void): So questions are: (1) Is there a way of adding internal wall insulation on a solid double brick wall using new "tech" which will enable me to skip the air gap? (2) Should I strip plaster off the wall? (3) What's the best material for battens? (4) Any tips on how/whether to do a service void? I'm going to wire the whole house with ethernet and rewire electrical, so this wouldn't be out of place. (5) I've noticed comments elsewhere by @Jeremy Harris regarding a need to do graded vapour permeability, starting with (as he suggests): "the least vapour permeable and the outermost layer is most vapour permeable". This approach seems to be pretty difficult with internal wall insulation. Or am I allowed to ignore the plasterboard for the purposes of this kind of calculation? Would love to be enlightened. Note: this was quite helpful: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/658604/BEIS_-_SWI_Innovation_Final_Report_-_FINAL_Approved.pdf

Hi all I'm renovating/converting an old pub into a house and the existing brickwork is covered with several coats of thick white masonry paint. I've been pulling the electrical fittings and wiring from the facade and it's making an awful mess. We're going to be changing some windows and doors, adjusting brickwork here and there as well as building new walls - all to be painted. What is the best and quickest way to remove this old paint from brickwork (some of which is 18th century) to give a good surface to repaint later? Thanks,

Hi, I am new here, I am trying to build/mend a wall at my home, but need to find these specific bricks to top the wall with in order to match the rest of the house. Does anyone know what they are called? or where I may be able to buy them? Thanks in advance!

Hello all, Hope everyone is well. Sorry if this has been discussed elsewhere on here, I searched but couldn’t find anything - but I have limited knowledge of technical building terms. A year ago we brought a Victorian property that had been empty for around 20 years. We had traders come and do the main jobs but are currently doing the smaller jobs and making the place in to a home. I want to build a small workshop - roughly 14 ft x 9 ft. The area I want to put it has three existing walls - two ‘garden’ walls and the other being the exterior wall to our kitchen. In the one corner there is also an old privy, I am unsure if it would be best to knock down or try and integrate it into the plan, it is a solid build. The garden walls are two bricks in width and around 6.5 foot high, in good shape other than needing to be re-pointed. It would be great to get some advice on areas before trying to move forward with attempting this, so thanks in advance for any help. Would it be possible to tie in to these walls and use them for part of the structure, and would I just use a wall starter kit? (The brick is accrington brick) The garden walls would need more height, I take it I could just add more brick to that to increase the height? Would I have to dig down and see what the foundation is like on the garden walls? I would be digging down to put a foundation for the new front wall, would I lay a new foundation around all sides? As they are walls built at the same time as the house (1901) I would presumably have to put in a DPC, and then build block internal walls? I know I will need to check with my local council but presumably I could build it as high as the privy? I’ve included a photos so people can see what the area and walls look like. One last question (for the moment) - a foolish project for someone with minimal amount of building experience? Cheers for the help and advice. Dave

Hi, We had an outdoor fireplace constructed and lit it for the 1st time last weekend. It was a roaring success (if you pardon the pun!). I'm concerned that the plastered walls won't stand the test of time and intensity of heat and was wondering if anyone could recommend a suitable material to line the internal walls to give it some protection from the heat. Thanks