Bitpipe

I believe so, I expect that they are scanned in also. Plenty of people have reported the odd invoice out of 100s being rejected or challenged. Get filing then now - took me a month of weekends to do mine when I finally opened the shoebox of doom

Great news @jack - I know this was a stressor for you. We had a very similar experience but just the 3 years after moving in Also had a few ropey invoices that I was expecting to get flagged up. I think it's dependent on who looks at your submission and how harried they are to get them processed, guess that after Covid there is more of a backlog so maybe they're just looking for basic compliance. Did you get a letter shortly after submission to say you qualified per the main form and subject to processing? That was the big relief for me as it meant all the dates etc were acceptable.

What is the house construction method and who built it? If it is traditional block / brick then the gaps are likely between the blocks and at floor / roof junctions, where the joists penetrate etc. Even TF will have lots of gaps. Add in gaps between door and window frames and walls, all intentional penetrations to the exterior (pipes, cables etc). Finally trickle vents in windows, extractor fans, poor seals in windows & doors, keyholes etc. Some of these you can address but many you probably can't. Good airtightness is not expensive but needs to be designed in and attention to detail at every stage of the build.

Had mine down since Jan 2018 and, when cleaned, looks almost as good as new. Like any exterior surface, if you ignore it it will get grubby. Get a jet waster with the patio attachment and give it a scrub in the spring. Stiff brush or blower good for moving leaves etc in autumn. Use a reputable trade - quite a few chancers out there. My guy had the bespoke 'candyfloss' style mixer. If they're using bell mixers, run away. That whole area was laid in one day so no joins.

I brought my paving level with the slab at the front door and rear sliders so have no steps. Ensure you have decent flashing at each threshold - ideally a lead detail that you can lap over the DPM that the door frame can sit on. You've not said what exterior finish you are planning - if its render or similar cladding, you'll have an air gap at the bottom (protected with inset mesh) that you'll need to ensure is clear. Render also needs a clear 'splash zone' of 100-150mm below and in front to minimize staining and algae growth. We achieved this by stopping the paving 100mm from the render and having a french drain around the perimeter that stops 100m below the render base so plenty of room for airflow. You will also need to protect any exposed EPS up-stand from rodent attack (from where they could gain access to your internal insulated frame layer) so an aluminium or heavy duty PVC detail or something like Ubiflex will work. Obviously if you're doing a brick or stone exterior, this will be sitting on its own foundation so no further protection needed.

While your airtightness is not bad (BR is 10?), it's too high for the heat recovery effectiveness of MVHR to be effective - 2 is normally the target. A passive house is 0.6 or less. I may have got my units mixed here as I am more familiar with ACH so ready to be corrected ! As @ProDave says, the biggest consideration will be the disruption of the retro fit. Even in a new build house, pulling the duct to every room through web joists is not a trivial task and you may well find obstructions from other services. The MVHR unit is ideally centrally located (but not essential) and needs insulated large bore (150mm) feeds to outside for air intake and extract, then manifolds for the internal supply/extract which feed individual runs of 75mm flexi duct to the room terminals. These are usually ceiling mounted, with a design that encourages airflow across rooms. Visualise the extracts in the bathrooms and kitchen pulling damp air out and the supply vents in bed / living rooms providing fresh replacement. Doors need 7600mm2 area at base to allow airflow between rooms. The efficiency comes from the transfer of the heat of extracted air warming the incoming air so you don't need to heat it again from scratch - unlike the cold air that comes in from your trickle vents. Extraction normally runs at 30% of fan speed and 50% for boost - triggered manually (switch) or via humidity sensors or electrically via bathroom lights / prox detectors or the hob extractor circuit (you may want to switch that to re-circulation). The system is balanced to provide equivalent incoming air, although the more airtight your house is, the less you can prevent cold air just being pulled in through the fabric or trickle vents. If specified and installed well, the system is fairly silent at the vents with boost being a bit more noticeable. Some add silencers to further attenuate noise. The unit itself should not generate much noise, depends what it is sitting on and if its isolated to any degree.

Yes, your health and safety based on the smell of some trades feet

The drip detail is key - where mine has gone green in winter, it is due to insufficient overhang from the roof above. It's pristine where there are proper cills etc. 50mm recommended for cills, 300mm for soffits.

I tried to standardise the location of mine so each room looked the same, especially in an open plan area where more than one supply is visible. However it took some trial and error as joist positions etc were not consistent. Settled on 600mm from one wall and 1000mm from another. TBH, once they're up they kind of disappear - my open plan kitchen dining has heat detectors, smoke detectors, supply and extracts and I rarely notice any of it. Just ensure you don't foul potential light locations for ceiling spots etc.

IBCs will quickly collapse if buried without a retaining structure which will cost you more than an underground tank. I did build an IBC DIY solution but happened to have a concrete retaining structure already built as part as our basement egress. As above, quite often you need some RWH to satisfy the regulatory water calc. I would not invest further in a parallel toilet flush capability as that will incur further cost (duplicate piping, plumbing labour etc) plus backup mains tanks etc. Use it for the garden with a cheap submersible pump and get the tank in the ground when your other groundworks are happening and there is plant on site.

I have a Ltd co for my day job, I pay about £250 to an accountant each month for services - this includes stuff like payroll, invoicing and the like so probably not relevant to your enterprise. However tax is a minefield. Understand your desire to retain control but if profit is your aim, getting planning is the biggest value add. Thereafter you're as likely to make money or loose money on the build itself as margins on that are notoriously slim. If you're using a main contractor then they will want a 20% margin on their spend as that's their business. If you're project managing then you 'save' the 20% but risk is inexperience consumes that buffer. Developers make money by land banking and then getting planning for selected plots. They then value engineer the resultant dwellings (spec and density) and despite the marketing, find the cheapest way possible to erect them which results in *very* variable quality (I'm being charitable). If you're aiming for a high quality spec and finish then expect that to eat into your overall margin.

Try and encourage your 2nd fix trades to take boots off at the door if possible. Grit and stones in treads will likely penetrate your protective layer and scratch the wood.

Have you been sniffing the paint thinners again?

Timber frame is very attractive due to the speed of getting a weather tight structure erected on site (a few weeks). It can also go up in pretty much any conditions (barring high winds) - mine was built in driving rain in November but 8 weeks from the start, scaff was down and the house appeared finished from the outside. For the novice builder (like me) it also means that you have all of the structural considerations, roof, internal walls & floors, temp stairs etc taken care of by one contractor (some even include the slab foundation). You can order windows and doors in advance off-plan and have delivered to site as the frame is completed plus TF can be a bit easier to adjust (within reason). You can then crack on with first fix in short order. However, airtightness requires the same attention to detail as above, there is nothing inherently airtight about a timber frame. Some contractors will include an airtightness guarantee in their contract. You also need to ensure that follow on trades understand and respect the airtightness layer (not to say it can't be penetrated when required, just needs done with consideration. Cost is the main drawback - TF is always more expensive up front and sometimes overall but I've not seen any analysis though that breaks down how the cost compares over the duration of an equivalent block build - I suppose the key variable there is time and what that is worth to you. I'd say the second consideration is the exterior skin - as mentioned above, anything load bearing (brick or stone) will require its own foundation and you won't get the same speed of completion. Render, timber cladding, brick slips etc would fix directly to the frame itself or to an outer skin of cement board on battens. From a mortgage and insurance pov, you should have no issues with TF.

+1, our oak stairs went in 6 months after we moved in. other advantage is there is no guesswork on the FFL top and bottom so they should fit! It's not just wet trades, dropped tools etc will create dings and scratches. Our engineered oak flooring went in ahead of painting as skirts etc needed to be fitted. I covered it in 3mm corex but it still got damaged - paint spills, knife marks (where the decorator had cut the corex away so he could paint the door frame and a big deep scratch from god knows what. Only evident when protection lifted and all trades long gone.

Getting this made into a sign and hanging it on the door.

We have those in each bathroom - standard 240v electrical connection is to the rear of the mirror / cabinet and they sit above the sinks so outside Zone 2. Exercised restraint on the bluetooth speakers and colour changing LED strips. We charge our toothbrushes in them, the de-mist function is handy also and the kids ones have clocks that they can ignore.

You will need do a SAP analysis by default but a PHPP analysis is a few hundred pounds if you're interested in approaching that standard. SAP will give you some indication and PHPP will give you a more accurate model. There is also a 'home grown' heat loss model floating around this forum that can help you estimate the space heating requirement. If your footprint / glazing area is now fixed (i.e. you have planning) then you only need to the hard work of defining the house once and then you can play with different wall and window U values. +1 to the MVHR - its needed to effectively ventilate an airtight structure without incurring heat loss but it's not effective at significantly heating or cooling. Consider making provision for a split air con (if you have PV, this effectively runs for free in summer). We have stack ventilation (Velux Integra in atrium) - works well to cool house in the evening during summer and then you can lock in the cool air for the following day. Keep in mind that in an airtight house, the stack needs a way for the air to get in at ground level so consider designing in an openable window that can provide this without creating a security issue. We didn't really consider it at design / build time but have found that opening a GF slider a few inches and locking shut is effective. Best would have been to have an openable window in our basement.

Usually that's on a slab where there is substantial insulation (EPS) under the structural concrete with the UFH pipes laid in the concrete (fixed to the mesh). If you're doing the traditional method where the UFH & insulation goes on top of an uninsulated slab then you need something to cover the UFH pipes and insulation and give you a mechanically sound layer to put your tiles on (and take the traffic from above).

We have windows from Gaulhofer with great external integrated blinds (from Roma) - they make a huge impact on privacy and solar gain - no curtains needed! @craig can advise on max span for that system.

I think any decent triple glazing solution will deal with road noise - if you're already considering MVHR and are planning to be airtight then you won't have trickle vents or other penetrations that would enable additional noise transmission. I'd say about 50% of our glazing is non openable anyway, mostly the feature windows (slots and column styles). Regarding UFH, if you're approaching passive standards of insulation and tightness then you may be ok with GF only - you should really model it first in a tool before you make a decision. What is your slab strategy? Think also on overheating, solar gain etc.

This thread has reminded me of Lost in more ways than one. Maybe the DHARMA Initiative installed the ASHP?

You can also call it in yourself if you think it helps your case, you just need to ask your local counsellor.

I can beat that, next door IS a planning consultant and conveyancing solicitor. Submitted a 10 page objection night before the deadline closed (in her husbands name). Poor planners had to rebut every point she made, none of which held any water at all. The few objections that planning raised themselves we were able to address. None of these were raised by the locals - mostly variations of the theme of 'I don't like it'.

Doing the garden mostly - all self build transitions from building to landscaping to plain old gardening. And like @Declan52, revisiting the odd compromise 5 years on and thinking 'Hmm, I finally have money again to do that properly'. Also just seen the Audi eTron GT though so it may put paid to that idea...