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Keymon's Achievements


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  1. Thank you @markc. So basically something like this, not deeper than the foundations would be fine. It is a much cheaper approach than breaking all the front tiled ground floor and lowering it
  2. So, do you reckon adding a French trench like this might be a bad idea?: https://www.1stassociated.co.uk/french-drains.asp https://www.ihbc.org.uk/guidance_notes/docs/tech_papers/French Drains.htm It was recommended by my Damp surveyor, see below
  3. Interesting. We have a serious damp issue in the front of the cause, because they raised the ground levels outside above the DPC level, they partially blocked the airvents, and we had the roof gutter (mine and neighbours) just pouring water heavily by the wall and the air vent. Also the soil had rumble and was touching the wood and bridging the DPC. And a pair of poorly old chimney foundations with all the rumble left behind. This house seem to be a book example have all the damp problems 😄 Then I dig the soil in that corner to check the foundation depth (btw, 450-500mm) and it was actually very wet, no water, but muddy and soft. Our damp surveyor advice was to extend the gutter to the main street (obviously). Restore ventilation and lower soil levels. Then either lower the front ground levels (break an bunch of concrete and tiles) or install a french trench at 400-500mm in the front perimeter. I was planning to install the french trench. Do you think the french trench might dry the soil? And if I install glasscrete, does it make sense to still do the french trench? Yes, that is what I thought! BTW, my neighbours have a concrete slab there. I think part of my damp issues, apart of all the other issues We are still choosing. The previous owners had a solid oak of 15mm flooring in the lounge. It is very damaged, but it is good quality. We were thinking to reuse it, but it means giving up UFH there. Do you think soild oak would do the trick with this ground? Then for the rear kitchen area, we didn't decide yet, but these tiles seem ok: https://www.stonesuperstore.co.uk/limestone-tiles Nothing really, just a normal north London residential street with terraced houses. In the garden/patio there is a small fig tree 4m away. This house is very basic and had been removed of any nice features, no chimney, nothing special. Had been heavily extended. There is not much to preserve. So basically the options I have are: Timber: breathable and ventilated, but not so energy efficient. Might require digging. Concrete, energy efficient, not breathable and risk of damp, requires DPC, requires more depth (450mm) But quick and all builders are familiar with it. Glasscrete, breathable, but restricts on flooring options. Long time to dry. builders are not used to it. Still, I think breathable and ecological are selling points.
  4. Sorry, I meant: I do not want to dry the soil. But I understood from your original comment "If clay you don't want to dry it out or it will shrink and cause you big trouble." that having glasscrete could cause the soil to dry. You mean for the screed, in case if I go for glasscrete or similar with the lime screed? Interesting. I am not doing the works myself, hiring some builders. Likely they will not be happy, but maybe they are OK?
  5. I described my current situation here: At the beginning the plan was to make all timber, then we considered concrete in the rear, keep timber in the front. But the architect says we won't pass building control with the current joists of 100mm, we need to replace all to get ticker insulation, and then we will need to dig more, etc. If we put concrete in all the floor, we would achieve a good u-value, but the recommendation then is to do DPC across all the perimeter. I reached the company. They say that. U-value of 0.22W/(m2K), can be done with 150mm Compacted Geocell + 100mm Lime Screed Price wise is ~6k, but 7.5k with the screed sand. The soil is mostly clay. How can it be dried out?
  6. Continuing my questions regarding floor structure. I had the option of timber or concrete. But I learn about this other system: Glasscrete, with a lime based screed: https://www.mikewye.co.uk/product/glasscrete-floor/#1511968619333-7006ff0e-6459 https://www.limecrete.net/wp-content/uploads/2019/06/Glasscrete-Installation-Guide-V1.pdf In theory it checks all the boxes: Solves the issues with the damp as timber (they claim) It is energy efficient, I can get a 0.22 u-value with 150mm+100mm. this is great because we have a 450-500mm foundation. It has all the pros of concrete. Cost wise, I got a quote for materials, almost 6k for 85sqm. I am not sure how it compares with concrete in terms of cost. I see the caveat of the drying time. They say 7-14 days depending temperature. Also, if the builders will know how to install it or not (although it seems fairly simple) What do you think about this system?
  7. Actually checked and it is 20x5cm joists with a 35cm between them (every 40cm). There is a gap as you described.
  8. One alternative we looked at is the Velux Dormer: https://www.velux.co.uk/products/space-makers/dormer What is your opinion on those? Do you reckon this could work without major changes?
  9. We had a previous bigger conceptual design (from other architect) with a loft as a L, which was meant to be under Permitted Development (<40m3). I am assuming that as it is much less, it should be fine. Anyway, I will ask the architect. And of course this would require a Party Wall agreement, etc? Unfortunately we already served notice for the chimney removal and roof replacement. That is annoying, the surveyor would likely charge me again Thx a lot for your response
  10. Thx for your answer! Yes, that is my next question. I wonder if these joists are even installed correctly. The joists seem just installed by the existing ceiling joists. No beam or anything. I guess resting on the walls? I am not in the property, but IIRC they are 15cm spaced every 40cm.
  11. Hello, We are in a Victorian house renovation. We plan to remove one load bearing wall in the kitchen, and that requires a steel beam. If relevant: the 1st floor joists will be at the level of the beam (not on top). The beam will be supported by 2 posts with pad foundations that will be built too. We also want to break and rebuild the existing concrete slab in all that area, due poor patchy construction. There is concrete at both sides, the old kitchen and a bath from the side extension. To reduce costs, and start early, I have somebody to help removing all that concrete before all the prior works start in some months time. But now I was thinking that maybe it would be convenient to NOT remove the concrete slab, as maybe the people removing the load bearing wall would need it to put the acrows, temporary load bearing studs, support for needles or whatever. Reading some sites like this one I confirm my suspicion (just found this): What do you think? Some photos and plans:
  12. Hello, We are into this renovation of a Victorian house. It has a reinforced loft (poorly built, but it has 15cm joists), but without any dormer window, just pitched roof. At first, our plan was to not touch the current loft, and focus on the rest. But due issues with the chimney (barely supported by timber), some old roof tiles in some areas, the need to retrofit membrane and add insulation, etc, we decided to just rebuild the roof and remove the chimney. And as we are doing that, we thought: Why not do now a dormer? Now, if we do this it means: Architect will need to do drawings, SE wants to charge again, and then build might delay our works? Cost wise I was told by a roofer like ~10k So my question is: Providing that the loft is already reinforced, how difficult would be add a the box for a dormer window, like below? Would it usually require a lot of structural work (ie steel), or would be the existing 15cm Joists be enough? or maybe it just requires duplicate the joists?
  13. Yes, so basically I though several approaches: Avoid the bifold windows, by running the vents in diagonal. The bifold is not that big. Put the vents under the bifold, by lowering the ground level in the front as I mentioned above. I do like it much, what if that rear area gets flooded! Add at least one vent to the roof I will discuss this with architect today and lets see what BC say 🤞
  14. Not sure if I understand the question. The reasoning to keep concrete in the back is commented here, but basically: it is already concrete, better insulation, works better with underfloor heating, and my neighbors have also a slab, so the DPC might be in bridge. No, not at all, i did not know that was an option. Happy to do that if it works, do you have any references on how this can be done?
  15. Hello, I have this terraced house, and we have suspended timber in the front and concrete slab in the rear. I am considering rebuild the concrete and keep the timber. The rear is 9 meters of concrete, so I want to add several telescopic vents (likely 4x or 5x, every ~1m or less) under the concrete to try to add as much ventilation as possible to the suspended timber. But we will have some big bi-fold doors at the end, so no space for all telescopic vents. At least one vent has to go under the bifold. Also: the rear garden is elevated, at same level that the internal ground. It is a bit lowered (15cm) within 1m by the wall, with some paved ground. This paved ground in the back, right now, gets flooded due poor drainage. Finally, we would like to have the same level between indoors/outdoors in the bifolds, so thinking to add some decking. So, I am considering: Lower the ground in the back (within 1m or 1.5m area), so the ground low enough to fit vents just under the bifolds and over the ground. Pave it. Add some channel drainage by the wall (or maybe a french trench). Add some composite decking, but by the wall above the airvents, add a open steel mesh. Something like this based on the drawings from https://www.pavingexpert.com/drain06 Then, the vents that are not where the bifold, just a bit higher... but no real reason for this, it is that it feels wrong having it under the decking Thoughts?
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