How big is all this 'utilities' equipment?

[puntloos]

A quick followup here - which is embarassing, but it looks like I didn't mention the reason for my question was how big a basement I need ?

I'm kinda figuring that a 2x3 should even suffice, maybe 3x3 for some extra space.. 

 

Does that make sense? All things being equal it sounds like hiding equipment into a basement would be a good improvement in quality of the house, and assuming 2500/sqm would make it not insanely pricey.. (or are there starting costs for a basement that don't factor into this 2500/sqm quote I had)

 

With of course the added question: will dropping ASHP and tanks etc into a basement cause me headaches later, for example if stuff breaks.. not *too* likely but at some point, lifting tanks in/out of such a basement will become an issue?

Edited May 4, 2020 by puntloos

[Bitpipe]

Basements can be quite expensive per M2 when small as there is a high fixed cost of mobilisation of plant. I accept that ours is large at 120m2 (external) but it does form the entire foundation of the house above. We experimented with 1/4 and 1/2 basement layouts but it was not that more expensive to go full size and the planners did not care.

 

In the end it came in at less than £1000/m2.

 

Is your basement planned to be habitable? Ours just looks like any other part of the house, apart from the plant room (2m x 3m) which is a bit more utilitarian inside. We have a full size oak staircase to ground floor etc.

 

As we needed an additional egress point to meet fire regs, the plant room is next to the external door which is up a flight of concrete steps to outside. At the base of the door is an Aco to as soakaway, we used this to route the UVC overflow, Condensate from MVHR and gas boiler is pumped up to ground floor and mains drains.

 

If we ever had a mega leak somehow then I guess we'd just pump it out the basement door. 

[puntloos]

1 hour ago, Bitpipe said:

Basements can be quite expensive per M2 when small as there is a high fixed cost of mobilisation of plant.

Yup, I assumed that there's some 'startup cost' and only after that it's a steady cost for every extra m2.. 

1 hour ago, Bitpipe said:

I accept that ours is large at 120m2 (external) but it does form the entire foundation of the house above. We experimented with 1/4 and 1/2 basement layouts but it was not that more expensive to go full size and the planners did not care.

 

We're pretty close to our neighbors though, my idea is that if I have a small central(ish) basement the neighbours wouldn't mind.. but indeed "FULL SIZE" would be much cooler.

As I understand it a large part of the cost is actually carting away all the soil?

 

1 hour ago, Bitpipe said:

In the end it came in at less than £1000/m2.

 

That's a shockingly low price... but perhaps it depends on your area? excluding the basement, what price/m2 did you end up with? We're expecting 2250/m2 with a theoretical basement addon of 2500/m2 (which was quoted for a 25sqm basement). should we be looking for another builder? (or a .. basementer?)

 

1 hour ago, Bitpipe said:

Is your basement planned to be habitable? Ours just looks like any other part of the house,

So to be clear you have divided it up with various rooms, perhaps a bathroom/toilet etc?

 

1 hour ago, Bitpipe said:

apart from the plant room (2m x 3m) which is a bit more utilitarian inside. We have a full size oak staircase to ground floor etc.

 

Very cool.. I wasn't planning on making it habitable really - obviously my "3x2m" basement idea wouldn't be.. but if eg I could get a full basement (about 100sqm I suppose.. ) for 100,000 I might strongly consider it ... if covid/brexit are kind to our finances.

 

 

1 hour ago, Bitpipe said:

As we needed an additional egress point to meet fire regs, the plant room is next to the external door which is up a flight of concrete steps to outside. At the base of the door is an Aco to

https://www.aco.co.uk/products/domestic-soakaway ?

 

1 hour ago, Bitpipe said:

 

as soakaway, we used this to route the UVC overflow, Condensate from MVHR and gas boiler is pumped up to ground floor and mains drains.

 

If we ever had a mega leak somehow then I guess we'd just pump it out the basement door. 

 

Yeah, I was thinking more about if a major water tank would die, is pulling it up through the stairwell even an option or would we have to dig it out?

[Bitpipe]

12 hours ago, puntloos said:

Yup, I assumed that there's some 'startup cost' and only after that it's a steady cost for every extra m2.. 

 

Not really, economies of scale mean that the cost decreases /m2 as the basement gets bigger - also gives you more negotiation leverage.

 

12 hours ago, puntloos said:

We're pretty close to our neighbors though, my idea is that if I have a small central(ish) basement the neighbours wouldn't mind.. but indeed "FULL SIZE" would be much cooler.

As I understand it a large part of the cost is actually carting away all the soil?

 

It's a variable cost element for sure.

 

Problem with having a basement in centre is that it provides no other function in supporting the house, you will still need a raft or traditional foundation. In our case, the basement replaced the need to have any other foundation so we saved £30-50k there.

 

12 hours ago, puntloos said:

 

That's a shockingly low price... but perhaps it depends on your area? excluding the basement, what price/m2 did you end up with? We're expecting 2250/m2 with a theoretical basement addon of 2500/m2 (which was quoted for a 25sqm basement). should we be looking for another builder? (or a .. basementer?)

 

I'm in SE England so while not central London, not cheap. Rest of house was probably closer to 1750/m2 - averaged out at £1500/m2 (2015 prices).

 

Basement specialists are almost always more expensive than regular builders - get quotes from groundworkers who will do the excavation and sub out the concrete works.

 

12 hours ago, puntloos said:

So to be clear you have divided it up with various rooms, perhaps a bathroom/toilet etc?

 

 

No wet rooms as it's complicated getting waste water back up to ground level for disposal. Chunked into four rooms, two are kids TV rooms, one is (notionally a gym) and the other a book / craft room. Those last two still full of junk tbh.

 

12 hours ago, puntloos said:

Very cool.. I wasn't planning on making it habitable really - obviously my "3x2m" basement idea wouldn't be.. but if eg I could get a full basement (about 100sqm I suppose.. ) for 100,000 I might strongly consider it ... if covid/brexit are kind to our finances.

 

 

https://www.aco.co.uk/products/domestic-soakaway ?

 

 

Yeah, I was thinking more about if a major water tank would die, is pulling it up through the stairwell even an option or would we have to dig it out?

 

You should not have anything down there that won't go through a door or up stairs. a 300l UVC fits fine.