Costings Damage Control

[Calvinmiddle]

8 hours ago, PeterW said:

 

So I take it you went the MCS route ..??

 

Gas boilers don’t like underfloor heating unless you put a buffer tank in so factor that in ..! Given you’ve said you want to have a big family friendly house, unless you go very big on the boiler, a combi will not cut it for DHW so you are back to an unvented cylinder. A 400 litre UVC with a 9kw ASHP has change out of £3k if you buy right, and it’s much easier to link into UFH. 

 

If you have a cellulose filled frame, heating is the least of your concerns !

 

I'd say even a revised heating cost of £5k is too much.  I have a gas combi boiler, buffer tank and UFH manifold inc pump and thermostat all and that cost me £1,700 in total.  The UFH pipes were in the slab by MBC (I was on clay so there is a round way a passive slab and clay for anyone else who has that issue).

 

Then a couple of other things -

£10k for plumbing - I spent £2k to the plumbing so not sure if your £10k is for?  Does that include taps baths etc - I see you have a sanitary section so probably not?

£8 for ventilation - if this is MVHR then I got the kit from BPC, fitted it myself (as others have said its a self build right of passage.  Its easy to do and as it's new the quotes that you can get u to quote are silly.  Two separate companies I worked out have a labour element of £4k for something that is at most 2-3 work for a couple of people).  After fitting it I paid someone to commission it to keep BC happy, that was about £250.  Total spend on MVHR £2,600.

 

To give you some background my house is a modern bungalow, about 110m2 my build was £1,938 but if you look at just the house and getting services to the house and not the silly amounts we paid on hire (we have steel plates in the ground for 18 months, I must have spend well over a £1000 to hire that should have bought it) on what I spent on block-paving hundreds on m2 as I was building in my back garden and had to sort out parking for the front house.  Well then it comes down to a more respectable £1,343.

[Jeremy Harris]

12 minutes ago, Calvinmiddle said:

 The UFH pipes were in the slab by MBC (I was on clay so there is a round way a passive slab and clay for anyone else who has that issue).
 

 

We're on clay. too, also with an MBC passive slab, so there are ways around laying a slab on clay and no need to go for the thermal inefficiency of a suspended floor (poorer because the space under the floor can be a lot colder than the ground temperature in very cold weather - so greater heat loss).

[Visti]

10 hours ago, Mr Punter said:

We have used 15mm Knauf Soundshield Plus in a recent development.  You will only need one layer.  It is a lot tougher than normal plasterboard - a good compromise between p/board and Fermacell.

 

Good shout! We've investigated Fermacell but weren't convinced the outlay was worth it. Thanks for the alternative

 

10 hours ago, oldkettle said:

As wall acoustics is included in "Walls" line why is there a separate "Acoustics" item worth quite a lot even including savings?

 

The separate Acoustics line is going into the floor (37m2), not the internal walls. The category could be better named I suppose!

• 5mm IsoBase R50 PC @ £20/m2 = £1,110
• VL-65 Acoustic membrane PC @ £40/m2 = £1,850

10 hours ago, PeterW said:

So I take it you went the MCS route ..??

 

Nope, that one is new to us. More research for us I guess! Thanks for the heads up on the UFH issues, we've had the same from our architect and are including mixer units and pumps with weather compensated control to address the issue.

 

We're not hugely concerned with heating other than not going overboard given the Cellulose!

 

8 hours ago, lizzie said:

Sorry I cant work the quote bit here but did I read correctly Visti further back on this thread as saying MBC slab and frame were not accepted by warranty provider Prremier Guarantee?

 

The frame is all good, it's just the use of a slab on clay that Premier wouldn't gaurentee!

[oldkettle]

1 hour ago, Visti said:

The separate Acoustics line is going into the floor (37m2), not the internal walls. The category could be better named I suppose!

• 5mm IsoBase R50 PC @ £20/m2 = £1,110
• VL-65 Acoustic membrane PC @ £40/m2 = £1,850

 

Wow, this is specialised stuff with a matching price tag! Thanks for clarification.

 

Edit: on a second look, is this the one? https://www.customaudiodirect.co.uk/acoustic-membrane-vl65-mass-loaded-vinyl Seems £40 per roll?

And Isobase http://www.domesticsoundproofing.co.uk/sound_proofing_prices.htm - £138.75 per 27.75m2?

 

Edited November 5, 2017 by oldkettle

[Visti]

MBC have offered to place UFH onto the foundation prior to pouring the screed even if they don't do the slab themselves, so we're likely take that option. As for combi's, we've been advised that they don't scale well with fluctuating numbers of people in the house and that their long tern reliability is questionable.

 

We'll certainly be installing the MVHR following everyone's recommendations here. We've estimated $4k cost to be on the safe side (we're awaiting quotes from 6 suppliers), the other £4k you'll see listed in the DIY column so we'd expect to 'save' that.

 

As for the slab on clay... we may need to take that up with the warranty provider again then. Keep getting told one thing by the 'experts' and then another thing in reality from everyone here. Just glad we're able to get that second opinion

[Calvinmiddle]

My warranty provider didn’t even question us being on clay as long as the slab was made to the SE specs they were happy.

 

Not sure why you have been told combi’s don’t scale well with fluctuating numbers of people, they are ideal as it’s hot water on demand, no need to store it, unless you are trying to run multiple showers at once.  But how often will that happen and yer man @Nickfromwales can tell you the best choice to deal with that.

As for long term reliability they are fine, tried and tested technology and every plumber will be able to fix it, not sure you could say the same if your ASHP going on the blink over Christmas.....

Edited November 5, 2017 by Calvinmiddle

[lizzie]

1 hour ago, Visti said:

 

Good shout! We've investigated Fermacell but weren't convinced the outlay was worth it. Thanks for the alternative

 

 

The separate Acoustics line is going into the floor (37m2), not the internal walls. The category could be better named I suppose!

• 5mm IsoBase R50 PC @ £20/m2 = £1,110
• VL-65 Acoustic membrane PC @ £40/m2 = £1,850

 

Nope, that one is new to us. More research for us I guess! Thanks for the heads up on the UFH issues, we've had the same from our architect and are including mixer units and pumps with weather compensated control to address the issue.

 

We're not hugely concerned with heating other than not going overboard given the Cellulose!

 

 

The frame is all good, it's just the use of a slab on clay that Premier wouldn't gaurentee!

we are on heavy clay with mbc slab.....could make pots out of our ground, its just awful, solid red clay, the dug out area was like a swimming pool for months, still have trenches full of water when it rains and our temp drainage channels are not clear.  Our slab is the typical mbc eps with steel, concrete and ufh.  I cant imgaine how much worse than ours  your ground must be if they wouldnt accept it. Hope you find a decent alternative slab.

[PeterW]

2 hours ago, Visti said:

Thanks for the heads up on the UFH issues, we've had the same from our architect and are including mixer units and pumps with weather compensated control to address the issue.

 

Errr.... that aint required either !! KISS on the controls, run the floor as low a temp (ie 27-28c) as possible and you will be fine. 

 

MCS is the accredited rip off  scheme that gets you a £3k ASHP unit installed for £9k with the promise of £200 a year back for 20 years...... 

[Jeremy Harris]

FWIW, I run our UFH with a flow temperature of around 25 tp 26 deg C, binned the weather compensation because it was a waste of time and did nothing useful and I run the ASHP at a constant 40 deg C in order to get best efficiency (long story told elsewhere here, but I experimented a lot and found a massive variation  in COP due to defrost cycling).  If we had gas I'd have used it, as it would be cheaper and simpler, would give us a good hot water solution,  plus would probably cost less to run than an ASHP.  Heat pumps are really for those who don't have access to mains gas, in my view.  The cost premium for an MCS install in order to claim the RHI for 7 years is daft - for us we would have paid around an extra £2k in order to save around £80 a year for 7 years, barking mad, really.

 

The floor surface is typically a heck of a lot cooler than with a conventional, high heat loss, house fitted with UFH.  Typically our slab surface will never be more than about 2 deg C above room temperature in extremely cold weather, and most of the time it will be a lot lower than this.  Because of the very low overall heating demand (typically we need around 500 to 600 W for the whole house in cold weather), zoning becomes pointless, mainly because so much heat flows around the house through open doors and natural convection.  One thing I found wasn't needed at all was complex heating controls.  I started off going down that route, with a control system that took account of the floor temperature, room temperature, outside air temperature, flow temperature and return temperature.  I spent months trying to fine tune this, then binned it and fitted a sensitive (0.1 deg C hysteresis) wall thermostat in the hall and a simple time switch to turn the heating system on in the morning and off in the evening.  The simple system works brilliantly well, and was cheap - less than £100 all in for controls. 

 

I've just discovered that I can probably bin the thermostatic mixer valve, too, as I've recently fitted a Salus actuator (around £15) to replace the slow thermal actuator that used to turn the UFH on and off with one that maintains a constant 6 deg C or so temperature difference across the flow and return, and that happens to be very close to perfect in terms of keeping our UFH temperatures about right.   @Nickfromwales put me on to them, in this thread:

 

Edited November 6, 2017 by JSHarris

[Gone West]

In our naivety we used a budgeting estimate sheet at the back of a self building magazine. We altered it to reflect our build and amazingly we are still within budget with little else to buy. We have spent more in some areas and cut back in others but overall we're pleased. As they say ignorance is bliss.

[puntloos]

Digging up the old topic.

 

@Visti - would love to see your current situation.. hopefully you’re (near) finished building?

I've created a topic around cost & cost control, and the associated spreadsheet would love to see your before/after etc..

 

 

[patp]

On 03/11/2017 at 13:53, lizzie said:

I dont really want to tell you how much over budget we are because it makes me cry......we went for mbc frame and slab option as was a fixed cost but beyond that the whole thing is a nightmare.  Budgeted costings we were given now appear to be fairy stories. I had budgeted for high spec bathrooms, kitchen and lighting and I did all that myself on quotes and they are as expected. The rest of it is an absolute joke!

 

I have things not being done corectly the first time round and then having to be done again (not contractors fault or mine its not due to client changing mind etc).  Our ground works came in at 52k plus 35k for a retaining wall, we had no problems in the ground so I cannot see where 52k went......we have yet to get services down to the house (they are at the gate inside our property) or drainage and then backfill around the eps....this is another 10k plus so we have over 100k for groundworks and wall and honestly its not that complicated or difficult. We have had a professional project manager on board from purchase of plot, I do all the running around and spend a lot of time finding things we need. I am not able to physically ‘build’ it myself.

 

If are lucky and control very tightly the remainder we will end up on a 180sqm single storey build at £550k excl plot and vat reclaim......thats an eye watering £ps sq m! We had budgeted £375 - £400k after qs costed it at 340k, architect thought 3ish so we thought our budget was reasonable. Its a very simple bungalow!.

 

Yes I feel foolish and very stressed and have no faith in professionals now.  Learn from the excellent advice on this forum and do not put too much trust in your professionals where your money is concerned, by the time I realised what was happening we were so far in it was hard to stop a lot of it. I have done what can........oh and we are projected to be six months behind for completion which is another 12k in rent!

 

Sitting in corner sobbing quietly.........

 

Good luck.

 

Liz

Just found this thread and Liz you are frightening me! How did it get so out of hand? We are building a bungalow of similar proportions to yours and doing much of it ourselves using subcontractors. 

[lizzie]

1 hour ago, patp said:

Just found this thread and Liz you are frightening me! How did it get so out of hand? We are building a bungalow of similar proportions to yours and doing much of it ourselves using subcontractors. 

@patp it would be as long as war and peace to try and write it all down here...suffice to say our hopes of coming in at 550k ex plot were very optimistic.  

 

I always wanted a Huf Haus but they are mega bucks...went for sensible priced tf alternative and it turns out I could have had my Huf Haus for what we ended up spending.

 

Our failing was putting trust and faith in professionals and every time we questioned in early months we were fobbed off and by the time we realised the extent of  what had been going on we were too far in to do much about it. I guess it cost us a good 50k on mismanaged errors and stuff plus the nigh on 50k paid for professional management.....plus some quotes for trades I didn't  sort myself seemed high......leave you to draw your own conclusions as to why and where the ‘extra’ went.......

 

Still got some things to get finished too......i.e. fascias, thresholds, garage internals.........

 

The stress of it all made me so ill, I ended up in hospital.  I don’t even want to think about it. 

[puntloos]

Yup, the above is what we are all trying to avoid.

 

I wonder if there’s a pointed set of questions everybody should ask their experts/professionals etc.

For one, many people we speak to seem to be quite coy about if they are including kitchens/bathrooms and their own cost in their ‘rule of thumb’ quotes.

 

“Sure, this will be 2000/m2, of course excluding my fee, tax, kitchens, bathrooms….”

 

Of course there’s a bunch of ‘luck of the draw’ here.. of course some professionals just exude dodginess and you (hindsight is 20-20) forced yourself through a hunch that this team is weird, but I’m sure quite a few people are well, normal humans, who unbeknownst to you fall on difficult times themselves and try to squeeze more $$ out of their customers to make it through themselves etc. 

 

I’m debating hiring my own QS and contract admin, whose sole financial interest is in costing things properly for me… but this by itself might cost somewhere between 10 and 20,000….