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Dudda last won the day on June 1 2021

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  1. This is a fairly big project. Do you've an architect or engineer on the job who'd have all the info and be able to make a call. Hard to judge steel sizes, centers, wind loads and forces from a photo.
  2. Having all those stats is pointless. The temperature will be more or less the same in every room. Particularly if you have MVHR. Remember Wunda are a sales company so happy to sell you additional expensive stats you don't need.
  3. Dudda

    Concrete slab

    The concrete is already poured. It's only a small bit required to replace the two bits of timber he intends to remove?
  4. 1x1m and 600mm deep is huge. Overkill and more than enough for the gates and you don't need steel. I'm currently using the exact same size pads (designed by a structural engineer) for a large steel frame outdoor canopy that's built on reclaimed land and less than 1km from the Atlantic so will also have huge wind uplift. If my pads are fine you're will be no problem.
  5. ...removed.... EDIT: Sorry mine were different. They were the screwless faceplates ones in the same brand. Yours are attached at the screw point which mine didn't have.
  6. You can just remove this plastic. I believe the idea of it is if you've damp walls or moisture in the walls the rubber/plastic separates the metal from the damp walls as this could cause the metal to discolor / rust. It's kinda like a washer. Just make sure the walls are very well dried out.
  7. The cables aren't an issue, nor is the water feeds. The issue will be the waste pipe. Having fitted them about 4 months ago the electrical cable was the longest (2.5 meters at a guess ), then the water feed with the waste pipe the shortest. It's fairly easy to extend the electrical and water feed. Edit: I've just checked the booklet for our washing machine. Cable is 2.0m. Water hose inlet 1.6m, Drain hose 1.5m. It also states for the drain hose "If required, the hose can be extended to a length of up to 5 m. Accessories are available from Miele or from your Miele dealer." Wasn't aware until now you could extend the drain hose that easily.
  8. I Correct I didn't use reinforcement mesh as it was non structural or 2nd pour. Buildup I've used is sub floor, insulation and then polished concrete. I can't think of a project off hand where I've had it as structural. The guy who sits behind me at work did do it as a main slab polished structural floor in his own house last year. I'd be a bit worried about it getting damaged. Otherwise no reason you can't do it. Put down a few sheets of ply for fear a block or lump or steel would take a chunk out of it. Also don't let the water in the underfloor heating pipes freeze and crack the slab.
  9. I've put polished concrete floors into a lot of projects. Huge polished floor to the atrium of a Performance Theatre, Several Universities Projects, lots of houses and even my own house. Many of the projects won prestigious RIAI Awards. I've also seen polished concrete floors by others go horribly wrong. Some put in the wrong reinforcement, some use the wrong mix, etc. I wrote the below for someone at work but is relevant for you too. If you've any questions on any parts let me know. Concrete The concrete is 35N10 which is reinforced with plastic fibres at 900g per cubic meter of concrete. As a polished floor goes in later it might need to also be a pump mix as you’ll have doors, windows and roof on. Whoever you get to do your floor will help input on this. Placing of concrete It’s not just the grinding and polishing of the concrete that’s important. The placing and power floating of the concrete is critical. Unlike a regular concrete floor, a floor poured which will be polished has to be super flat and power floated for hours after. Very few people in Ireland can do this correctly. Formwork for steps and other edges has to be perfect and have 45 degree edges to allow trowels into the corners. Little things like dragging a vibrator, shovel or rake through a floor when placing the concrete the wrong way will result in the drag mark being visible when the floor is polished. These things may not be visible to the untrained eye but are flaws in a lot of cheap or poorly installed polished floors that can never be fixed. Spend time and money on this part as a poorly poured floor can’t be fixed by grinding and could make the errors even more visible. Crack Joint These have to be around every 6 meters max and are a saw cut made the day after in the concrete about 30-50mm deep which is later filled with a flexible mastic. Don’t have any areas too small as they could rock like paving slabs. Don’t have them long and thin either as they can crack in the middle like a seesaw. If you have a few pipes in the floor, eg heating pipes coming from a manifold it’s a good idea to have a joint here. It’s also good to line these up with any columns you have. Hide them under lightweight internal stud walls and have them at all doors, etc. You have to think about underfloor heating pipes and ensure they’ve sufficient coverage before cutting the crack joints. That’s where the thickness of the floor is important. Expansion joint Not to be confused with a crack joint these are flexible day pour joints and are also positioned above expansion joints in the structural floor below. As a result they’re slightly wider than a crack joint but again are filled with flexible mastic. For a house you probably won’t have one however we had one on a larger project I worked on a major project. Coloured Stone This is optional. I’ve done it in some projects but not my own floor. Make sure you get the contractors to quote for 4-5 samples if you plan on using coloured stone as you don’t want to get a claim later. You can pick whatever stone you want and also the size of stone. Usually they’re sprinkled over the top during powerfloating. They can be mixed through at the concrete plant but you’ll use a lot more coloured stone and it will be a lot more expensive. Glass which can also be used has to be lead glass as ordinary glass can shatter when grinded. Slip Resistance The slip resistance of polished concrete usually complies with all regulations. Like any regular floor it can be more slippery when wet. Additional grinding and polishing doesn’t necessarily impact the slip resistance of the floor so thinking a shiny polished floor will be a lot more slippery isn’t right. As it’s a domestic situation I wouldn’t worry about this however if it’s a public building you’ll need to include in your specification a slip resistance pendlium test to be carried out at the end of the project to prove the floor is safe. This is a useful document to have in the safety file should someone slip in the future. If you want to get it carried out for peace of mind you can. Sealing Make sure you ask in your quotes for sealing the floor after it’s grinded and polished as the concrete is porous and will absorb tea/coffee spills and heavy traffic if not sealed. The sealing will make the floor a tiny bit darker but in my opinion is worth it. Protection Include in the spec for the contractor to protect the floor after its poured for the duration of the works. We had two layers of cardboard over the floor for three months. It dired out more in areas where it wasn’t protected and at joints but once exposed the variation disappeared. Just ensure it’s well protected everywhere particularly if its not yet sealed as any paint spills etc, will destroy it. Grinding and polishing You can very lightly grind the floor and then polish it as normal if you don’t want to expose aggerate or alternatively grind it to expose the aggerate and then polish it. Grinding a floor is time consuming and therefore expensive so include for grinding the floor to expose a lot of aggerate and for a lot of polishing. You can then later decide with samples not to grind as much or go for a reduced polish. If you don’t specify the amount of grinding required they’ll assume a very light grinding with no aggerate revealed. The floor will be grinded in stages starting at 10 grit working through 15 grit, 25 grit, 50 grit, 100 grit, 200 grit, etc. 800 grit is matt finish and 1500 grit would be a medium shine with 3000 grit a high shine. If you want lots of stone aggerate exposed they’ll spend longer at the 10 and 15 grit before moving up. Reinforcement We used a plastic fibres reinforcement. You can get thin ones and heavier ones but the heavier ones can appear if you look closely in the finish. It’s 900g per meter cubed that use used which is standard. Don’t use steel fibres and don’t use steel mesh. I researched a lot of failed concrete floors and one major issue with steel mesh is when they cut the crack joints they don’t cut through the steel mesh so the floor can’t crack at the crack joints. The joints are still reinforced and therefore crack elsewhere. Perimeter You’ll need flexible insulation 12-15mm thick around all perimeters and at columns, service popups and penetrations, etc. Don’t use rigid insulation as this won’t allow the slab to move and therefore risk cracking. Another issue is with stone walls which are very uneven require thicker flexible insulation. If you intend to dryline do this after the floor is poured and you’ll hide the perimeter insulation easily. Thickness Our floor is 100mm thick and that’s the optimum. Don’t go below 75mm as below this is too thin and you’ll risk cracking. If the floor changes thickness anywhere you’ll need additional crack joints. For example if you’ve steps, ramps or around all recessed matwells as you have a change in thickness in the concrete. Services All electrical trunking and mechanical services should be cut out of the insulation below the concrete floor. If a 50x150mm electrical trunking was placed on top of the insulation the concrete would crack over the trunking. Where we had several pipes close to each other in the floor we had to include a steel plate to rest over to ensure the concrete remained 100mm think and didn’t flow down between the pipes increasing the depth but also preventing the slab from moving. Underfloor heating This works great with polished concrete floors due to the thermal mass of the floor and the slow release of heat. It’s important to have the floor well insulated so put in as much insulation as you can afford otherwise you’ll be paying to heat the ground under the building. Another key point is to ensure the underfloor heating pipes are firmly clipped down to the insulation as any pipes which become loose or if the plastic staples become loose they can be exposed or damaged in the polishing of the floor. Also you’ll be cutting into the slab for the crack joint and if the pipes rise a bit you risk cutting them.
  10. Dudda

    2022 Update

    Give them a ring. Have the planning reference number at hand and the name of the planner that did the planning report or signed the grant.
  11. Dudda

    2022 Update

    In terms of working with Dublin local authorities (or any authorities in Ireland) you need to phrase the letter something like "we assume the enclosed updated elevation satisfies planning condition number XX, however if not please let us know." That way when they don't get back to you it's approved. If you wanted you could send in a letter along the same lines. "In relation to the revised elevation submitted on the XX September 2021 we assume this meets the planning condition number XX as we haven't received further correspondence on this matter". The local authorities in Ireland (it probably varies and is more an issue in Dublin) are under resourced and so poor at replying to communications that a new law for planning applications currently under discussions will require the planning authorities to reply and agree within a certain timeframe.
  12. No regulation on what a suspended ceiling void needs to be. You can have it 20mm if you want. It's about what size do you need to hide the services. If you've 100mm waste pipe then it's probably going to be 130mm or so to allow for the pipe and fall.
  13. If they're at large centers, eg 1200 or more, and you've plasterboard between them, then no as the fire won't jump between them and spread easily. However if the glulam beams are holding up a floor above then it depends on the size of the beams as they have to support the upper floor level in a fire for a certain period of time if someone is stuck up there. If the beams are oversized then it will take ages for them to burn and loose structural integrity then they could be fine and don't need clear fireproof instrument paint. Your engineer can tell you this.
  14. Depends if you're trying to stop the spread of flames through the rooms which the plasterboard would fix or the surface spread of flames which it wouldn't. Generally this isn't accepted (again depending on use and location).
  15. Two options. Either get fire proof ply which they usually pressure pump fire protection chemicals into or you paint it with clear fire instrument paint. Most people go the paint option. Either option will be more expensive than plasterboard. In one project I worked on with exposed joists and sarking boards which needed to be fire rated the QS had a great cost saving idea. My drawings showed instrument paint but they suggested fire proof sarking boards as it was cheaper than painting. I agreed as visually they were similar. Problem was the fire engineer said the joists also needed to be protected. The whole roof couldn't now be sprayed with fir instrument paint as it would void the warranty of the sarking boards so each joists had to be hand painted. It worked out more expensive. Do you're research thoroughly first before starting or committing.
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