saveasteading

That's sensible. % of cost is a bad idea. Better get a fixed quote. That's untrue. Better just tell them that's your offer.

They don't build cavities well either, which is why I like full fill rock-wool. No mortar can get dropped down the cavity. If there is a way of pretending the insulation isn't right then I have missed it.

I think I need something clarified. Are you classing a groundbearing slab as a raft? It isn't reinforced , as there is no bending, and only has crack control mesh. Warehouse slabs are not rafts. They are usually uninsulated because they have heavy loading and an unheated, or reduced heat, space. I am suggesting a very simple slab on the ground. No reinforcement needed but I would add the minimum. Then the insulation of your choice : actually I have a hunch towards 100mm eps with 100 pir staggered over it. Gut feeling again, but based on many decades of prior thought and prejudice, plus stuff picked up on BH.

Because it's an easy answer and takes ten seconds. Yours included. One of Parkinson's laws applies. There you are that's yet another one.

He would spout Shakespeare. But David would praise you for providing an insect haven.

Thanks for your summary. I feel it is a tiny bit biased towards expecting a raft to be better value. I confess to having the contrary expectations. Also that I would expect to PM myself, using fairly ordinary local builders. That is a lot of value.20% of more. To tweak yours. 300mm eps = 150 pir as insulation. Similar cost. Less dig pir. Raft needs 2 layers of heavy ish steel, compared to 1 layer of the lightest. Raft has a deepened perimeter snd at walls. Raft is poured in the weather. That's a risk. With my contractor hat I don't like delay or risk. The detailing for insulation is standard and easy. Of course raft people say otherwise. Now. I was a professional estimator for yonks. I'd rather fancy doing a roper cost comparison but haven't the time. Gut feeling. 20% more for a raft. Maybe 30%. Justifiable if not PMing it. As for trees. I quickly looked at the tree tables but couldn't see hawthorn. The nearby founds will be no deeper than 1.2m, the rest at 1m, i'm pretty sure. Forget piling too. It won't be necessary. Other people can advise. Are there any special measures to protect the eps at the perimeter or for the interface to the walls above?

And allow insects a nice winter hibernation spot. Up to you.

The hawthorn hedge at 7m isn't a problem, even for clay. My immediate thoughts. Keep it simple. The 500mm of soil has to go. Strip footings to 1m below ground level. Brick or block to floor level. Hardcore ( pref type 1 but any well graded stone.) 300mm th. Concrete slab 100mm with mesh. Or thicker if the builders aren't superb. At this stage proceed with superstructure. 200mm pir. 60mm screed with ufh. And this is the finished floor at 160mm above ground. Add dpm and another layer above the pir. That should be very much cheaper than a raft, and is non specialist.

Don't count on it. Proper cover is very expensive. Especially PI. I've known many cases of businesses taking out the least that can keep them legal / get them work. They should have provided the info to you before starting the work. I had a roofer once who's cover excluded any work higher than 4m. Because that was cheap....small ads in the Sun.

So would I. But perhaps the first one fills and overlows to the second. Thud the first tank is fuller and easier to pump. And yes, a settlement tank before them. Divided by a porous manifold. maybe a net.

I look forward to reading the progress of this argument. Photos of the hedge planted? Every plant died? Was it all dug up again? Perhaps the planners need to stipulate 'plant a living hedge, look after it, replace any deceased plants, and do this for 5 years after occupation, after which apply to get the permission signed off. Presumably the condition was acceptable at the time. Plant a hedge and I'd be interested in a blog about it.

Tell your friend that it may be a big deal ...or not. A condition can apply prior to, during or post construction. All are conditions, so all must be complied with or it does not have approval. This may raise itself when another application is made, to the same property or nearby. It would also arise during the enquiries stage of a sale. If the issue is so minor that nobody cares, or circumstances / fashions have changed, then he can make that case.

We will put in a tank between the house and soakaway, be part of the journey if you will. I'm thinking 3m3. For the pump, I Can choose to immerse a battery pump with a hose or to a simple standpipe. Or a quaint village pump type thing. Perhaps both. It will be fed from 180m2 plan area of roof, so it will take 15 mm of rain to fill it. July rainfall is 61mm. Maybe I should go 4m3. I'll look on 'marketplace' for a tank. But for now, I'm going to think of whether ibc × 3 is sensible. At the right price, £25 yes. But people seem to want £50 or more. Then how to stop it caving in when empty? It should never float because it will be full in wet weather. But a couple of spikes and a cable is simple. All suggestions welcomed. The BuildHub rwh for cheapskates/ the sustainably minded. @Temp @marshian What would you do differently another time?

I agree you delay this. They are expensive but essential if it goes to adjudication of court. At this stage you are getting together the essential information. I recall sitting with an expert witness who was effectively interviewing me to support our own case. It was worthwhile in itself, in getting our case tested. After 2 hours or so he said that I knew much more about it than him and that he would now write his report. A few pages cost several hundred £. 2. Get a move on. The other party might be rearranging their business and then disappear this one.

Building it inline as part of a new drainage system of course has benefits, as the work is small. A new potable tank seems to cost £400 or so for 3m3. How much water cost would that save? 20m3 per annum x £2 x 10 years.....£400. It doesn't need to be potable quality. An old IBC will be £50 x 3..plus some pipes. But will that survive underground or does the plastic degrade? Plus it would need to have a cage to bear the ground load, and some cement board too. Any other suggestions?

I have 3 small water butts. They run out for about 3 refills worth in SE summer. So it is simple and does fine as a pragmatic compromise. But I will put 3m3 underground as part of a new conversion system, plus an ibc in a concealed area. Better to design a garden to not need much water, and no buts about it.

That's for domestic use, fully plumbed in to the house. Which I don't advocate. I'm just suggesting that you might want to catch the rain for the garden. Agreed re ibc tanks being far cheaper. I've done that for a new bus station, with 3 of them linked. With the tap slightly open in winter it also slowed flow to the sewers. But ugly.

OK for taking the extremes off an attic or shed. Look at the thickness of the foam layers. Then at the air gaps. Can they combine to the same effect as the same thickness of eps of Pir? The effect of a shiny surface can only work once. Energy bounces back off the first surface it reaches into the medium it is against. There is a distinct lack of independent testing. They seem to have their own.

Yes, if it is only about money. But it is 'a good thing' in reducing water consumption i summer and outfall to soakaway in winter. You may have water for the garden when others have none, in a hosepipe ban. In parallel could work if you get the levels right and the water to flow where you want. Or change that chamber into a holding tank, with overflow going to the soakaway.

I agree with @ProDave. It's good to do the homework on the issues but being so precise is giving them something to argue back against. Not fit for purpose because it is falling out. On the speculation front. I don't know what happens with premixed mortar. How is it delivered and stored? How long does it sit around before use. It is possible that it had gone off by the time it was used.

@nod I sent a personal message and was happy with the response seeming genuine. So I'm happy nobody is being conned, but your concern is valid.

More info will help. Do you know what the insulation material is? Is it plain brick, cavity fully filled, brick, plaster? Is there damp internally generally or just at some locations?

That sounds like rather organised crime. Surely the chancer types are ignorant of such techniques and make up the majority of thieves? However that's a very good point re thieving big stuff on remote sites. Eg construction sites and farms.

Excuse my ignorance. What is it and why might one want it? Obv I shouldn't be allowed to do it.

It is entirely to support the pipe and nothing to do with rats. Because gravel flows into the space and fills it completely, it resists any forces from the pipe, and adjusts to suit any movement. It is also easy to lay as a bed to the precise level required. Rats shouldn't want to stay in there once it is up and running, and all sealed. There shouldn't be any food in there either. But they explore everywhere and it will seem like a ready-made burrow until the tidal waves appear.