Benpointer

Sorry if I missed this earlier but have you posted any info / plans etc. on your intended build?

I am now convinced our issues arose from the floor surface getting damp again from the plastering. The house humidity went up to 98% in the few weeks the plasterers were skimming, despite open windows and the MVHR and UFH both running. It's now back to 40%. I can't criticise the tiler for not proceeding though - we have had floor tiles laid on a too wet floor before and many of them 'popped' over the following years - a nightmare to fix, so best avoided.

They are 3980mm x 580mm for a 4000x600 opening.

Checked with our decorator, he says you can do either but in our case it was a further coat applied with the roller.

It’s now six months since we broke ground and it's fair to say we’re very pleased with the progress since we began. We have of course been very lucky with the contractors we’ve had working on the project, right from the start with the great groundworks team and that’s continued pretty much throughout. And we’ve largely avoided unexpected surprises and delays. That was until a couple of weeks ago when we found that our screed was not dry enough to start laying the floor tiles https://forum.buildhub.org.uk/blogs/entry/1122-week-24-juggling-with-the-plan/ Never mind, our decorator Steve Brady rescheduled some other work and came in a a week early. Decorating It took Steve and his son Tom just three days to mask and spray throughout - and what a transformation! If you are willing to have one colour throughout this has to be the quickest way to go. Our thinking is that we will no doubt repaint rooms or individual wall in a range of colours in time but to allow us to move in as soon as possible we were happy to stick to one colour. Steve and Tom sprayed a mist coat of diluted Armstead trade white straight on to the plaster followed by another coat of Armstead, then two coats of Dulux Diamond Matt, mixed to ‘Dimity’. He then rollered over the walls which should help if we need to touch any paint up in the future (touching up spray finished paint by roller or brush doesn’t really work apparently). The results look great and we feel that it gives us a really solid paint job. Spraying does use a lot of paint though, especially with our vaulted ceilings and high walls: 80 litres of the Armstead and then 80 litres of the Dulux. Steve and Tom our decorators: The final rollering: Tiling Finally, by Thursday this week the screed reached a level where our floor tiler Steve Hillyard felt it was safe to start laying. The relatively drier weather we had last week has no doubt helped, and with the MVHR system running and the UFH on low the air humidity in the house dropped below 40% (the day the plasterers finished it was 98%). Our delays have no doubt disrupted Steve’s schedule and he’s worked through this weekend to catch-up, which we really appreciate. The first tiles are looking great. They are 900mm x 600mm Italian porcelain tiles from Pietra Wood and Stone near Bath. Focus for the next two weeks Floor tiling Bathrooms - my brother is with us for two weeks to make a start on out bathrooms. Cladding - the scaffolding we need the high cladding is now in place. Deliveries - bathroom, kitchen, appliances, door casings… all planned for delivery in the next couple of weeks. 2nd fix electrics - should start in the next two weeks. Dashboard: Contractor days on site this fortnight: 14 Contractor days on site since build start: 396 Budget: No change - still a bit over budget but within contingency. Plan: Still on track to move in by Easter 2026. Issues and worries closed this fortnight: The screed is dry! Current top issues and worries: Nothing too concerning, which nice.

Apols for bumping this one - still pondering whether to paint the sand and cement render that is below DPC, and if so with what? If anyone has any experience or suggestions they would be gratefully received. Thanks!

Good steer John. We used Cosy this way in our previous house and it worked well. Just to conclude though - no need for the Heatmiser Neo Hub?

We are about to enter 2nd fix when all our 7 wired room stats and 2 dew-point floor sensors will be connected via our two 8-port Heatmiser wiring hubs to control 16 loops (most rooms have two or more loops). Today's dumb question: Do we also need a Heatmiser Neo Hub, and what would it give us? If it's simply smart home capability, I wonder if we actually need that. In our last house we set the room stats to a comfortable level and ran the UFH 24x7 52 weeks per year (it was never demanded during the warmer months at all). That worked fine. I guess with solar and batteries, plus an Octopus agile tariff, we might want to control the UFH with respect to battery charge, solar output and variable tariff rates but we could probably do that through the Panasonic HP app if needed. Any thoughts? Thanks

Why do I wish we'd put the insulation on top? It would have simplified the build (easier to lay insulation over the top than fix from below) and left us with the open web joists to run services (especially MVHR ducts) through. Tbf ours our pitched roofs not flat so may not be relevant to you.

No, but I wish we had put additional insulation on top, instead of underneath our roof. We did the latter because of concerns about roof thickness aesthetics but with hindsight and a bit of careful design we could have addressed that.

Can you not raise a money claim against them?

We've had this debate on another thread John. We're note zoning, at least not from a heat pump perspective. We do have room stats controlling loops to specific rooms because we want some rooms (bedrooms, pantry) to be cooler than others (bathrooms). (If you consider that zoning then ok.) I believe your view is that we could control this be setting loop flow rates at the manifold but frankly, I can't be arsed with that 'tweaking' - I'd rather just use a room stat. The 'buffer' is really a volumiser, it's recommended by Panasonic: Volumiser: in the open primary circuit (when all heating – cooling circuits are closed) it is recommended a minimum water volume of at least 30 litres is included.

The plan for the two weeks just gone was to complete the plastering and start the floor tiling. No issues with the first part, our team of plasterers have done a great job, see below. The floor tiles arrived more or less on schedule, and the tilers Steve and Kev turned up as planned. However, when they checked the floor humidity to confirm it was ready to tile, the meter showed it was slightly over the required level. I am a little unclear of the actual moisture numbers but their meter was showing an amber bar when they really need it to be green to be sure it is safe to tile. The screed has been down for 63 days in an airtight house but that screed was 65mm thick on average so it was perhaps unsurprising it was borderline with the 1 day per mm drying time not quite being met. (I have also seen a suggestion it should be 1 day per mm up to 50mm and 2 days per mm over, which would be 80 days!) Also, of course it has been pretty humid outside throughout that period and the plastering has necessarily added more water inside the house. No doubt that vapour control layer has been doing its job too preventing internal moisture getting into the structure. To mitigate this we have had the UFH heating running very low but the plaster was drying too fast when we tried increasing the UFH temperature. We have also had the windows open a lot of the time and for the past week we’ve been running the MVHR system to ventilate the house. But despite that, the floor is not quite dry enough. Of course, the plan is all very tight and was meant to be: floor tiling last week and next, spray paint w/c 17 November, then 2nd fix electric and plumbing is booked from w/c 24 November. So what to do? Disruptive as it must be for the floor tilers, they were very good about it and suggested seeing if we could get the decorator in a week early and then they’d work long days to try to get the tiling done by the 24th or thereabouts. I called the decorator (another Steve) and after he had made a few calls he confirmed that he could indeed come in next week, Monday to Thursday. So that’s the revised plan. Hopefully by Thursday the floor will be dry enough to start tiling. If not well… that’s a bridge to be crossed later. Plastering Despite the frustration of the (admittedly tight) plan being disrupted, we are taking comfort from the fact that the boarding out and skimming is all complete. Dan, Sam and Brandon, our team of local plasterers have done a brilliant job for us and we’d be really happy to recommend them to anyone needing a plastering team in the Dorset, Wilts, Somerset border area (PM me if you want their details). Brandon, Sam and Dan: Cladding The end of last week also saw the return of our chippies Alan and Chris who made a start on the timber cladding. We’re using Brimstone Ash from Vastern and Alan and Chris made a start with the soffits first. Focus for the next two weeks Spray painting throughout. Floor tiling Cladding (we are going to need some more a scaffolding for the high cladding, so that is hopefully coming next week). Dashboard: Contractor days on site this fortnight: 29 Contractor days on site since build start: 382 Budget: No change - still a bit over budget but within contingency. Plan: Still on track to move in by Easter 2026. Issues and worries closed this fortnight: None Current top issues and worries: Unsurprisingly: Will the floor be dry enough to tile?!

Good point Rick. The steel ducts are actually on the 'warm' side so don't need insulating (though we have popped some acoustic insulation offcuts around them just because we have them. The 'cold' side ducts are Zehnder ComfoPipe 160mm pre-insulated ducts as shown here:

A principal role of the project manager is surely to deal with the unexpected - for example, when a key team member is ill and out of action. But what happens when the project manager is laid-up? Following an ‘incident’ (all my own fault), I have spent the past week unexpectedly in hospital. That was definitely not in the plan. Fortunately I am home again now but largely ‘confined to barracks’ for the next month or so. At the moment I cannot even visit the plot, although I hope to be able to make the occasional visit over the coming weeks. As you can imagine this is deeply frustrating. Worse still is the realisation that my lack of hands-on project management has made absolutely no difference to the pace of progress (well actually, it may have increased without my involvement, tbh). Curious. The main thrust over the past two weeks has been carpentry, ventilation ducting, boarding-out and plastering. And fortunately we have two excellent chippies and a great team of plasterers in. We really have been very lucky with our trades; here’s hoping it continues through the remainder of the project. Mrs P. has been magnificent during this period too, keeping the show on the road by constantly stocking drinks and snacks, regular runs to Screwfix, keeping the site tidy, as well as fixing all the internal acoustic insulation. Not to forget planting all our new trees! All while running back and forth to the hospital 20 miles away to keep the Project Manager sane and stocked with essentials (edible food mainly). So, great progress has been made despite (or because of) the absent PM, and we continue on plan. Ventilation ducting and caprentry I had some wild idea that Mrs P. and I might fit the MVHR ducting but the least said about that the better. Fortunately, as noted in the previous blog, our chippies Chris and Alan stepped in to run the ducts very neatly to all the rooms. Even though it’s a new build we’ve found it tricky to work out how to run the 14 semi-rigid 75mm ventilation ducts from the MVHR to all the rooms whilst avoiding obvious ‘boxing in’ sections around and across rooms, which would have detracted from our desired clean lines. Partly that’s because it’s single storey and most of the ceilings are vaulted right up to the insulated roof. If we did another build (Mrs P: “We’re not!”), I’d definitely look to use those open web joists to good effect for ducting. But in the event it’s been left to Chris and Alan to ‘magic away’ all the ducting behind invisible false walls, whilst impacting the overall room sizes as little as possible. And a splendid job they have made of it. The ducting plan requires seven supply and seven extract ducts attached radially to two 8-port manifolds close to MVHR unit itself. We chose to site the manifolds 3m away from the MVHR unit in a void above the kitchen alcove which will hold our built-in ovens, connecting the manifolds to the MVHR unit with 160mm rigid steel spiral ducts, which themselves needed to be hidden away behind a false wall in the utility room. Acoustic insulation As noted above, Mrs P. is an absolute whizz at fitting this. I'd like to think that she's enjoyed it but, um, I'm not brave enough to ask. Anyway, it's going in to every stud wall as soon as there's board on one side to fit it against: Boarding-out and plastering The main thrust over the two weeks has been the room by room boarding-out and plaster skimming. 12.5mm board to the walls, and 37.5mm insulated plasterboard to the ceilings. The plastering team - Dan, Sam and Brandon - have been great. Particularly pleasing is that they are alert to problems and think about the finished product, raising any questions or concerns so that they can be resolved rather than simply plastering over them, so to speak. For example, questioning whether a pendant right by a wall rather than centrally in the room was what we wanted (it wasn’t, the cable had been dropped in the wrong place). We are now about 2/3rds of the way through the plastering and it's making an amazing transformation - turning a house frame into something that begins to feel like a home. Tree-planting Remember all those trees delivered in the last blog? Well Mrs P. got them all planted with the help of our landscape man Ashley, and they are really looking great. Focus for the next two weeks ...Will be on completing the plastering and then our floor tiler Steve should be making a start on the 170m2 of porcelain floor tiles. We thought about using engineered wood in some rooms but in the end we decided to have the same limestone effect tile all the way through and will use rugs to provide additional interest. Eight pallets of tiles are due to be delivered next Tuesday. Dashboard: Contractor days on site this fortnight: 42 Contractor days on site since build start: 353 Budget: No real change - still over budget but potentially using a little less of the contingency than previously. The benefit of an absent PM possibly 😉 Plan: Still on track to move in by Easter 2026. Issues and worries closed this fortnight: N/A Current top issues and worries: A fortnight ago I said "Nothing too pressing - it'll be something we haven’t thought of, probably." Well that was prescient! Current top issue: getting myself back fully fit - otherwise, how will the project manage without me?!

We went with Paul Thorney at Air2Heat, who was originally going to provide an umbrella MCS service but for various reasons (mainly to do with the warm feeling we got about his phone and email pre-sales support) we asked him to do the whole supply, install and commission for a price we though was fair, and we got the £7,500 grant back within a couple of weeks. If you're thinking of a DIY instal but fancy the £7,500 grant, speak to Paul about his umbrella MCS service - you'd still be gaining over £5k after allowing for his commissioning and certification costs.

Tbf some of the music choices of our contractors are definitely a H&S risk. Hearing and Sanity that is.

Re the unplanned extra photo at the end, just clarify Mrs. P. up a stepladder is not the next big issue or concern! 😉

Two weeks since the last blog and there’s a lot to cover - but lots of pictures too, so persevere! The main issues and concerns two weeks ago were 1. how well the airtightness test would go, and 2. keeping ahead of the plasterers. The good news is: both of those concerns can be consigned to the bin. Airtightness As previously reported, we had engaged Aerobarrier to test, spray their magic mist, then retest the airtightness of our house. Prior to their visit they asked us to send video walkthroughs of the house. Because of concerns we had about how well the airtight membrane had been fitted and taped, which the videos did nothing to dispel, I asked Josh from Aerobarrier to plan some extra time for them to re-tape some of the wall ceiling interfaces, for an agreed price. The Aerobarrier team duly turned up as planned - Josh plus two others. After a few hours taping the house, the initial airtightness test gave a disappointing if not entirely surprising 3.2 ACH - go enough to satisfy Building Regulations but above our target of 1 ACH. But after running the acrylic misters for a couple of hours the airtightness improved to 0.8 ACH - an 80% improvement which we are obviously very pleased with. Aerobarrier left the place quite tidy, they had masked the horizontal surface on window frames, door handles etc. The only weird result was the screed floor was left as sticky as a dodgy Wetherspoons. A week later and the stickiness has more or less gone though. No photos of the process in action I’m afraid, tricky to get inside with all that mist flying around. First fix electrics …is now complete! Power, lighting, PIRs, smoke detectors, data cables, room stats, TV… there are a lot of cables threaded round our walls. We’ve had a great team plugging away at this for a few weeks - Nick, Martin, but especially Darren, who installed the majority of cables and boxes, have done a super job. Carpentry In parallel our two chippies Chris and Alan have been making sure various false walls and ceilings have been put in place ready for the plasterers. They have also fitted three of our four pocket door frames - just one more to install next week. Somebody also needed to run the MVHR ducts and fit the vent plenums to the rooms the plasterers were planning to start with. This seemed like a golden opportunity for Chris and Alan to acquire some new skills. I am not sure it was high on their wish list to be honest but they cracked on with it nonetheless. Regular free breakfast baps still works wonders when you’re asking people to go the extra mile. Acoustic insulation I could see that Mrs P. was itching to get involved with something and fortunately someone needed to push all the Rockwall acoustic insulation in to the internal stud walls. Luckily as it’s Rockwall rather than glasswool no further itching was involved. Anyway, Mrs. P has done a great job, as you can see. Plastering All of the above were things we needed to have done (or at least done enough) for the 8th of October, which is when our plasterers Dan, Sam and Brandon were booked to start. They duly turned up as planned and we had enough of the rooms ready for them to get started. In the plan, all the carpentry work would have been completed before the plasterers started but they seem happy enough to board out then skim one room at a time as the carpenters keep ahead of them. The initial focus has been on the boarding out bedrooms 1 and 2 and the bathrooms and the early progress bodes well for the rest of the task which we aim to complete by the end of October… ready for the floor tiler! In other news… Our timber cladding has been delivered. We’re using Brimstone Ash from Vastern near Swindon https://www.vastern.co.uk/timber-cladding/brimstone-ash/ which we will be having fixed vertically. Once Alan and Chris have finished all the internal work required for the plasterers the plan is for them to move on to the external cladding - assuming they haven’t had enough of us by that stage. More breakfast baps may be required! We have also had a number of trees delivered, which Mrs. P. was strangely much more interested in than she was in the pallets of plasterboard or multi-finish skim! 🤷‍♂️ And finally, I have bought a new toy… a Topdon infrared camera to plug in to the iPhone. Cue quizzical look from Mrs P. “er… and you needed this for what exactly?” Good question Mrs. P, but I have at least been able to check that the UFH loops are all working: During the next two weeks... … we hope to be getting plastered! Dashboard: Contractor days on site this fortnight: 32 Contractor days on site since build start: 311 Budget: No change - still over budget but within contingency. Plan: Still on track to move in by Easter 2026. Issues and worries closed this fortnight: How well the airtightness test will go. Keeping ahead of the plasterers. Current top issues and worries: Nothing too pressing - it'll be something we haven’t thought of, probably.

I'm blaming autocorrect! 😉

Yes, sounds very similar. I also have a concern about the paint blistering, hence the question - in the hope that someone has done this a few years ago and report on their experience.

Ok, we may have made a mistake but we've had the concrete block wall below DPC rendered with a sand and cement render. We did this because concrete block walls don't quite cut it aesthetically. I am confident there is no bridging of the DPC. Above the DPC sits our timber frame finished externally with a ventilated cavity and either STS cement boards + thin coat render, or vertical timber cladding. There is a 45mm horizontal gap with inset mesh between the rendered blockwork below DPC and the external wall finish above DPC. The DPC itself overhangs the rendered blockwork by 20mm or so, so we're confident there is no bridging issue. The blockwork below DPC supports a ventilated block and beam floor as well as the timber frame, and is thus itself ventilated on the inside. My question is: How to finish the render? Can we leave it unfinished? Can we paint it with a breathable masonry paint like Sandtex? (We're thinking a darker colour might look better.) Will that below DPC render inevitably 'blow'? Thanks as ever for any thoughts or suggestions. Some pics. Before: How it looks now:

Wow! That's impressive! Very rapid build start to finish. We'd seriously considered MBC but in the end went for a cheaper option. Overall, we're happy with our decision but I seriously doubt we've saved that much money overall.

We hunted around for the best price for 75 sheets of 18mm class-3 exterior ply and because and my local builders merchants, Sydenhams, came up with £28.74 per sheet ex VAT. Very good boards they are too. Best of all they have kept the price for the extra sheets I have bought in 1s and 2s. Appreciate you are nowhere near a Sydenhams but I assume other local BMs might do similar for a bulk order.

Plan is to hang the door to open outwards (with a suitable locking mechanism!)