Ferdinand

Welcome to the forum and thank you for such a clear explanation. I will leave others to comment on the PWA aspect, but I question that 200mm gap you are suggesting. That seems to me to be the wrong width because it is not easily maintainable: 1 - ISTM that there is not space for you or your builders to build it tidily (bloke plus trowel and room to work is more than 200mm). For such a narrow gap you or your builders will be working overhand (ie from the inside) which will make your new wall a probable mess. 2 - Once it is built it will be impossible to maintain your wall and the ground in the gap. eg What will you do when it fills up with autumn leaves which bridge the damp proof course, or should building work ever be required down there,or if a child gets stuck, or if you or your neighbour get rats and the ratman needs access? My suggestion is that the gap should either be zero, or at least 450mm (= 18 inches), which is just wide enough to get in to sweep out etc. 600mm seems to me to be more sensible, as you can then do something with it such as ladder storage etc. The only exception I would make would be where your gap is short enough that you can reach down it with your arm plus a sweeping brush, rake etc. and reach the end. I would suggest reducing the width of the extension by 300mm to make the gap wider. You can recover much of any lost inside space by using a thinner design of wall ... eg by using Celotex rather than Rockwool insulation. Alternatively talk to your neighbour about butting right up - even if you are not needing the PWA it is good to talk unless there is a good reason not to do so. Ferdinand

Obviously do not cut corners on asbestos unless you are a professional yourself. My dad was killed by asbestos from (we think) being a supervisory architect on a short 6 week project 40 years earlier.

No one seems to want to say how thick it is. What do they use in forklift warehouses?

@Weebles Re the gas, do you mean 'cap' or 'disconnect' ? If you mean cap so you can strip the gas appliances and pipes to weigh in for cash, then any gas man will do it at the meter in1 minute. If you mean disconnect at the road then you are into your provider or network operator as discussed above. Ferdinand

Great news @RichS It would be useful to know the key points that convinced them, if you could post a summary. Ferdinand

@vivienz No problem :-). Bat welfare comes above your desire to build your house in the hierarchy of priorities, so you either a) Cater for them or b) Show that they have gone and will not be back. On this thread about build costs @Barney12 explains about his bat related expenses, which is perhaps a worst case. If you want some amusement, this hyperbolic Telegraph column by Nicholas Coleridge is nicely written. There are horror stories, but I am sure that in the large majority of cases it is all more or less OK. F

This is for the Little Brown Bungalow project, but may be more useful here in future for reference. The current floor buildup is, from the bottom: Concrete raft. 300mm or so ventilated void. Suspended wooden floor. Underlay + carpet or similar. The void contains some water and gas pipework. The question how to maintain this access in future. I am planning a 'floating' floor ... though not completely floating. The intended buildup is something like: Concrete raft. Ventilated void. Insulation between joists - 100-200mm rockwool. Suspended wooden floor. Vapour / air membrane 50mm Kingspan between battens. It is from Seconds and Co so the battens are to be safe. 18mm OSB, screwed down to battens. Underlay. Click fit laminate or carpet, depending on room. The question is how to do the floor so that I can get at the gas / water piping if necessary. I am able to adjust the buildup if necessary to a degree. I could potentially leave the battens out altogether or not screw them or the OSB down depending on the Kingspan which I will find out when it arrives, and insert a separation membrane to ease movement. Any comments are most welcome. Cheers Ferdinand

Products such as Celotex CF5000 allow this with pir, but Foil Faced EPS seems very rare. https://www.celotex.co.uk/products/cf5000 Ferdinand

If you look on eg Money Super Market Self Build or similar, there seem to be a surprising number of banks and Building Societies that deal direct. Worth a look? As for a broker, I would suggest asking the most experienced and qualified (MRICS?) staff member at your local independent self-owned estate agent for 3 recommendations, which was how I found mine a few years ago. You will pay about £500-£700 for going via a broker (subject to London Area higher prices). Based on your other conversations, I would suggest cultivating that relationship over time. If your project goes ahead you will be sitting facing your good architect and your main contractor dealing with a nearly £1m project, and a half-created relationship with a local expert from outside your project bubble who knows your Council and their policies and staff inside out will be an invaluable standby. If you only have a bit of work from them ("please spend a couple of hours looking at my plans before I commit" or similar at a key point where you have been asked for feedback) for a couple of hundred on a couple of occasions, a good tip or leading question could save you thousands or tens of thousands. IMO one hole in your setup may be a knowledgeable local informal 'mentor'. Ferdinand

Travis Perkins De Walt Drill / Driver clearance. Here De Walt have a good 18V hammer drill driver and 2x1.5Ah X-RAY batteries for £120 inc VAT. This is the model which has been my mainstay since 2013. I paid £150 in a Screwfix Sale, and has been excellent. https://www.travisperkins.co.uk/DeWalt-DCD785C2-18V-Xr-Li-ion-Compact-Hammer-Drill-Driver/p/550474 Ferdinand

@vivienz My comments / suggestions. Not formal advice. Ecology Report + Planning Conditions I think reading the existing ecology report will give you a grounding in bat issues if you read it cover to cover, as there is likely to be 50% boilerplate basics included which is the same for every report. You also *must* be familiar with related Planning Conditions. The report will contain: 1 - An assessment of your site. 2 - Recommendations as to what you should do. 3 - Probably an expiry date beyond which the report is out date. Technically that means that you need a new report or the Ecologist or Bat Man to give you written evidence that it continues to be valid, which would require a further payment. It is often routine Councils to not notice such dates in subparagraph X.I.1.a (iii), so you may dodge that one if you keep quiet. The Council Planning Permission will have a Planning Condition telling you what you are required to do, which typically would call out to the report. If the Condition is different to the report or only mentions parts of it, you should take note of the Planning Condition on the Planning Notice. Demolishing under Existing Planning Permission You need to understand your bats and trees and all the other reports before you decide that. For bats: To work out what you do under the existing PP, you need to talk to the relevant Council person (Planner / Naturaiist / Conservation Officer etc - find out who), and probably the Ecologist advising you,and ask them. You may get lucky as pointed out above - or not. If you work with the existing PP, make sure that your new Planning Application is consistent with what you do. And check with your Planning Officer, Council Nature person, and your Ecologist / Bat Man to make sure you are OK. Your new Planning App will need to relate to the situation you have now created by doing work, and of course they could set different Planning Conditions. I have never expored Council attitudes to doing half of one PP, then then second half of another one. It feels a bit "Here Be Dragons". When you are are actually doing work with bats you will need a Licensed person to supervise / carry out the work. You may also need a specific License for the item of work from English Nature. Again, you need advice from your qualified adviser, who may organise it for you. Intellectual Property One other thing you need to know is whether you can use the Intellectual Property in the reports relating to the existing Planning Permission in the new Application. If you do not have permission, then you will either need entirely new reports, or to pay the authors for the right to use them. You may get away with the Council by eg just mentioning the previous report in the Design and Access Statement, or you may not, and you may receive expensive demands from irate Consultants. I am interested in others' experience here; I have never tried it. If you have permission, it will be recorded in the documents around the sale of the plot. The best scenario is when these reports have been "Assigned" to you, which means that you have become the Client for those reports and benefit from eg the Liability Insurance of the author. Alternatively you may have just been granted the right to use the reports, or not have the right. Hopefully the person who sold you the plot included a clause giving that right to their purchaser in their original contracts with their consultants, which was then written into your contract with yoru vendor. What did you (or your solicitor) negotiate when you bought the plot? My suggestion is that if you find you need a Licensed Bat Man, or new reports, then talk to the same person who wrote the first report - you will save as they already know the site. You may get free reuse of the existing report as a perk. Ferdinand

This is a passive slab, to be more exact @JSHarris' passive slab (sequence of photos). It is a concrete raft foundation (= less deep digging) incorporating about a foot of insulation such that, when combined with similar walls and roof, your heating bills are approximately zero. It is a shallow hole over the whole house footprint filled with hardcore and blinded (smooth layer on top to be less nobbly) with sand, and insulated under the concrete pour, perhaps with ufh and other bits and bobs poking out (soil pipes etc). Then the house is built on the layer of insulation usually as timber frame, with cladding. In the pic, all the black polythene round the edge is covering special insulation blocks that meet the insulation in the walls. A number of people here have used this (which is from a company called MBC) or similar systems.

There was a good education on how not to do self-build on Homes under the Hammer this morning. It is the first example in this programme, and about 20 minutes in for the outcome. http://www.bbc.co.uk/programmes/b08ny6bx My favourite: 'I photographed all the noggins, and then deleted all the photos. Then when my plumber asked where my noggins were, they were harder to find." And a lot more. To be fair, they just about broke even ignoring their own time, and plan another one.

Will pm you.

Don't mention them first !

Your mouse has a Critical Job Detector installed.

I am not saying that it will take that long .. just raising a flag not to be too optimistic. eg When you want to demolish it you have - I think - to serve a notice and wait 6 weeks. So you need to be running that in parallel with other things or it could delay your Critical Path. When you submit your PP it will be 12 weeks for approval as a minimum, plus any extra time they and you take, plus the time it takes you to do what you need first, then perhaps recruiting a contractor and negotiating, then wait for their slot to arrive, then build it, then ... and so on. Then there may be seasonal things. If you end up having to do tree or bat things, the times can be limited by eg nesting seasons. I have not heard of firm price. The important thing about Fixed Price is that the contractor takes more of the risk (eg labour rates going up) and changes are more expensive, so you need to minimise those and have a design you commit to fully up front. If you have newts in your river then the Nature People will be all over you with measures to protect them. That you have one PP already with no issues is a hopeful sign. Ferdinand

>I plan to move out and rent, I'm hoping it will take a year. Hmmm. I would say be mentally prepared to take 2-3 - just in case, you understand. Of course I could be wrong, but specific expectations can be a curse. Do you know where you are with Planning Gain taxes - Community Infrastructure Levy, Section 106 and so on? On 500sqm near London that could normally run to six figures or nearly six figures, and you need to know that you will get the self-build exemption from CiL and it has some elephant traps around starting development and perhaps around demolition / rebuild (others here will know). Also, suggest not posting too many identifiable photos before you have planning locked down, unless everybody who might see it here and react is already fully aware of what you are doing. Do you have newts? We love newts on Buildhub. Probably do not answer that :-). Is this one for a fixed price contract? F

A couple of old photographer tricks can be helpful for stability.. 1 - Is a normal monopod, which fixes the Laser Measure in one dimension. 2 - The other is a loop of string called a String Tripod. Put one end under your foot and attach the other to the measure. Does the same thing. A posh string tripod with have a thumbscrew fitting into the tripod socket on it. F

Quote for the above is now in. It comes to about £3200 including fitting, which I make £170 per sqm for 19 sqm. A run through on Double Glazing on the Web gives a range of £4200 to £6500. Ferdinand

Welcome.

@Adamantium welcome. You sound to have the skillset necessary to develop the further skills you will need as the project develops. It would perhaps be worth you investing some time in skimming all the blogs and comments on this site (there are only a couple of hundred articles) as that is where the blow by blow detailed problems, solutions and wrinkles over time are explored - then reading the ones that seem relevant in depth. I would also suggest looking at @JSHarris's blog which is offsite, as his angle is at the other end of your spectrum ... he learnt about the construction specific aspects of project management and did it himself ... which will give you some insights into the stuff your architect and main contractor are doing under the hood. Jeremy's comments on overthinking are superb. I think it is important to invest time as well as money and make sure you keep your eye on what to you are the key aspects - the best architects in the world only know this if you have gained the knowledge and then take the time to tell them what is important to you. Time is cheaper than money to correct the things you missed by not spending the time :-). The other resource I think I would recommend is the House Planning Help podcast and related blog - he now has nearly 180 45 minute (ish) episodes which are perfect tube listening covering a huge range of relevant subjects. All that and whatever else you find should give you a hinterland to be on more equal terms with your architect and contractor as time progresses. Best of luck. Ferdinand

@recoveringacademic et al. The technique I was taught was to shine the spot at the ground by your feet, then gradually moving it towards the thing you are measuring while watching the spot. THen it is easier to track since you never lose registration. I have the green Bosch and it is OK for medium distances. Beyond that it is a target or glasses - have not tried sunglasses. Will see if my reactolites in my normal glasses help. As for being horizontal I judge it by the distance up the target from the ground. There is a huge tolerance on the level ness of the beam before the distance you are measuring changes materially. So no need to worry about a few inches or feet of wobbling as long as you get a reading off the right thing. Being 100mm out vertically with the spot at a distance of 10m only alters the measured distance length by 0.4mm. 300mm of inaccuracy in height means 1.2mm out on length. Being 100mm out vertically with the spot at a distance of 5m only alters the measured length by 1mm. Both are less than the roughness on the face of the brick you are probably holding the measure against and acceptable unless I have my trig in a twist. (Can someone who's laser measure is not lost in space give me a real world check on that last point. There is something counterintuitive about it. But I guess the existence of 7 x 24 x 25 as a Pythagorean Triplet means that if you measure length diagonally across a 7 x 24m garden by mistake after too many cocktails you will only be out by 4% or 1m on length which is more accurate than the General Boundary rule applied to your fence.) Ferdinand

CATFLAP !!!

@aims This is my opinion not advice. Answers first: Stamp Duty is nothing to do with the mortgage. It is on the value of sold Land and Buildings, with a special rate of +3% which applies unless it is eg your main residence or in other exempt categories. However, this has a threshold of 40k which you may be under depending on what you do. I think CGT should probably not apply to gifts. I am not clear what happens if you dad dies before 7 years without asking my accountant. CGT is paid on the increase in value of an asset while you hold it. You get an allowance (11k?) each year, and you may be surprised how small the liability may be; it was on mine last time. For a start it is part of an asset not the whole you are dealing with, and extra pieces of garden are not necessarily worth as much as we might think. Then if you build something I think you can offset costs against the gain, and if you did the usual self-build spend-up-to-the-final-value thing, there would be no immediate gain anyway to pay CGT on . And comments The advantage of a valuation is that it allows you to justify your decision to the HMRC just in case someone asks. It is a cheap insurance policy. There is always some variation in values, even amongst 50 identical houses. For a potential plot, if you reduce the risk by eg consulting with the Council pre-app service and getting a "probably yes", or any other amount of things, that alone may increase the value. I think you may need an accountant as well as a solicitor - or talk to a place that has both. Once you procure a solicitor, ask the solicitor whether you need an accountant (or vice versa). IMO it is wise to use a solicitor to do land transfers if you do not do it regularly yourself - but use them to learn the process and check all the details. Any professional should give you enough time to ask some questions (write them down first) as to whether you need their services. I would start by sitting down with the experienced person (ideally MRICS) at the closest independent EA and talking about options. Lead with what the plot with PP or a house would be worth and ask enough supplementaries to understand your options, then ask for a recommendation for a solicitor if you need one. The karma quid pro quo is that you give them a shot at selling it later should you proceed. I think you need to be clear about your objectives - is the aim (1) for your dad to give you some money by utilising his spare garden (2) for you to build a house to live in or (3) for you to get the experience of doing a project. If (1) it is possible that there will be no extra gain by building a house. Occam's Razor perhaps says you get the PP for your dad, he sells the plot and gives you the money. Then lives for 7 years. If (2) you need to find out about things like moving in with dad first (extension? Good way to gain experience), then building it in your main residence garden. If (3) - fair enough, but do not necessarily expect to get that much extra money in the short term over selling the bare plot as well as learning. The biggest advantage of building a house I can see is that you have a larger sum that will tick up in value each year you keep it. 25% over 5 years on 500k is a lot more in cash terms than on a 150k plot. If you are in West London more intensive developments may be possible. Long term rental or similar investment for decades? I am aware of people who moved out of a nice area 25 years ago for a similarly priced premium house elsewhere and the London house is now worth 4 or 5 times the other one. Ferdinand