Retired doctor looking to demolish and build new 6 bed home with a builder …

[7dayworker]

I’ve looked at a load of articles and YouTube videos and heard material price rises and labour inflation is an issue.

im just going to planning and would like a new home and air source heat pump and mvrh for a 4000 sq foot build .

land is expensive here so the 60 year old house will be demolished. The builder is a friend . 
my queries are around light and sound proofing as well as ducting the underfloor heating and landscaping , to remove bamboo.

if any builders can throw me a lesson learned, that would be great. 
the architect thinks a full brick exterior is the solution , but I’m not sure of the bulky impression that creates .

we have a purbeck stone cladding to our front.

I am new to this and apologise with so many questions .

[ToughButterCup]

First things first. Is PP a foregone conclusion? Have you researched similar applications? Does your planning department have a thing about (say) Purbeck cladding - you hint at bulk: might the planners agree with you? 

The lesson I'm hinting at is - if you can't point to other instances of applications (and planning decisions) similar to yours,  then you are more exposed to whim. Don't make yourself an easy target.

[7dayworker]

Thanks . I have read the planning submissions and reports for the area and all have increased the size and this has been accepted for planning . One failed due to loss of character in our conservation area and going to appeal.

I expect the pre-planning will clarify issues

[ToughButterCup]

Excellent. Could I now sound a cautionary note about friends working for you? ...You did ask ...

 

In this context, professional detachment is extremely difficult:  be the issue mate's rates, or employees drinking tea half the day or cash flow, or whatever, there's built-in stress. Every single build has at least one - often more - Oh FFS moment.  That's when professional detachment is a god send.

 

I'm not suggesting you find another builder, just a little nudge.

[Bonner]

+1 working with friends can be very trying and easily lead to the end of a relationship, both personal and professional. Best to maintain as professional a relationship as possible on the build, then go out for a pint on Friday night and talk about footy! Make sure you have got a good set of drawings, clear specification and explicit agreement on who does what. Leave him to do his bit and avoid the (overwhelming) temptation to micro manage.

[ToughButterCup]

Next question: related to MVHR.

To what extent is your builder comfortable with the concept of air-tightness? What experience does he (she) have? And if none, then how are you going to manage that education process ?  For me, it was an impossibly steep learning curve.

 

Please excuse me if this is a bit 'forward', but here's a list of resources about air-tightness-champions  (I loathe the sobriquet  too)

Airtightness search results

 

 

(Before Gollum gets me, there are  search engines other than google)

[JohnMo]

+2, about friends, different rates of work and expectations, for a couple of weeks is ok, for months on end, could drive you up the wall.

 

Are you down sizing to a six bed house for retirement?

 

UFH is easy enough, it sits above the ground floor installation and in the screed.  Have a u value circa 0.1, this will limit downwards heat loss. 

 

You mentioned outer skin of building, how are you building the structure?

 

Light, big windows are great, but the downside can be over heating.  Even with big overhangs, the sun when it in the west and low can cause over heating, so watch for that.

 

We have a well sound proofed internal walls, but a door open circumvents all that.  So I would not get to hung up about it, if you have 70mm stud walls, use 25mm sound insulation job done.

 

All the things mentioned about airtightness, contractors in the main have no clue about airtightness, don't care, don't understand the issue, generally think you are daft wanting an airtight house.  

 

Bamboo, lots of weedkiller, one that attacks the roots

[Marvin]

Be sure it's bamboo, and not something else... .

[Bitpipe]

We demolished and rebuilt. It removes all the risk and uncertainty related to the previous fabric and gives you the opportunity to build a modern, energy efficient and comfortable replacement home. If you get it right, your running costs will be minimal and it will be a very pleasant environment year round.

 

Airtightness and high levels of insulation are key, given you're in the south coast you'll need to focus more on managing summer overheating than winter heating.

 

Sadly a lot of the construction industry, architects included, are still stuck in the past and will design and build to a minimum building regs standard with minimum insulation in walls, trickle vents in the windows, radiators everywhere etc. You can do better so do your research now.

[Bitpipe]

Also, +1 to avoiding working with friends.

 

A large refurb a few doors up from us has gone to pot as the 'family friend' builder was obviously taking liberties and was difficult to challenge. We walked past the site daily to see little ever happening whereas ours was always a hive of activity and we did the whole project in just over a year from demolition to moving in.

 

Two years in and theirs is still a shell, family have moved back onsite in a caravan (to save money obv) and a local builder is now trying to catch up.

[SteamyTea]

Welcome.

If you choose your insulation type carefully, then it can help reduce noise transmission.  Same with glazing.

Just to make the distinction between energy use and technology type used clear, the building 'needs' an amount of thermal energy to keep it at the temperatures you like, regardless of how that energy is supplied.  So thermal modelling is important.

 

Now, you being a Doctor has reminded me of the 1990 Bootle By-election when the RLMP got more votes than the SDP, so to quote Scream Lord Such when asked if they would merge with the SDP, "We could use a good Doctor".  It is the same here.

 

I used to live in Lower Parkstone, we called it Upper Sandbanks.

[Bitpipe]

10 hours ago, 7dayworker said:

..... a new home and air source heat pump and mvrh for a 4000 sq foot build

... ducting the underfloor heating...

 

Digging into this requirement a bit deeper....

 

Given your location and earlier comments on overheating risk you could consider an insulated slab design where the entire structural ground floor of your home (assuming you don't have a basement) is isolated from the surrounding ground using high density insulation (EPS 200+ grade).

 

The UFH pipes are cast in the slab removing the need for additional layers of insulation and screed and usually run at a fairly low temperature (35^o). This works best when the house is highly insulated and airtight, reducing the space heating requirement.

 

If you use a ASHP then in summer this can be run in reverse to cool your slab on warmer days. Given your sunny location I would ensure that solar PV is part of your design as it will be able to make a significant contribution to your power requirements in summer. I'd also make provision (really just ducting & services initially) for split air conditioning should overheating become problematic.

 

MVHR is very effective at delivering fresh air while minimising energy loss but given the intentional low airflow of these systems, it's not an effective means of moving heat (or coolth) around the house. That said, in a very efficient home (approaching passive standard) then it can act as a trim function.

 

Think also on external blinds for east & south facing windows as this prevents heat penetrating the house early in the day.

 

Our building (similar size to your proposed one) has a twin wall timber frame construction with the cavity insulated with pumped cellulose. This delivers great insulation but also has high decrement decay and good soundproofing properties. Your windows will also be key, triple glazing will deliver excellent soundproofing and tend to have the necessary seals and gaskets that help also.

 

Also important to remember that any external facade (brick, stone, render, timber cladding etc..) can be combined with any structural system (block, timber frame, ICF) and the various structural systems all have their own pros and cons wrt speed of construction etc and all tend to balance out cost wise - the structure is usually only 20% of the building cost.

 

I guess the big takeaway here is - design and build using the system and spec that gives you the house and performance you want - don't be confined to only what your builder friend is comfortable with and don't fall for the story that other systems are 'too expensive'. Do your research and understand all the pros and cons.

 

Good luck, you'll get lots of help here - between us we've probably used every type of build system and made every mistake there is to make

 

[7dayworker]

Thanks so much for the advice all round . The builder has hired the architect to draw and submit the plans .They will also do the building regs.  all at a cost of 15k

The house was valued at 1.5m , but is 60 years old with extensions  3000 sq ft and needing a new roof , windows etc.

most people here demolish and build new as I know over the 40 years I’ve lived here. 
estimated cost of build 900k . There are 3 rooms in the roof space with velux windows.  It would be difficult to know what the sale value of the new build would be.
we have a easily adapted ground floor bedroom , bath etc if we get ill. We hope to have grandchildren come to stay and are hoping to sell if we get into decrepitude , but not for 3 years which relieves CIL and of course vat.

we are borrowing with a legally drawn loan from family , who will be first to get paid their proportion in a sale.

[7dayworker]

24 minutes ago, Bitpipe said:

 

Digging into this requirement a bit deeper....

 

Given your location and earlier comments on overheating risk you could consider an insulated slab design where the entire structural ground floor of your home (assuming you don't have a basement) is isolated from the surrounding ground using high density insulation (EPS 200+ grade).

 

The UFH pipes are cast in the slab removing the need for additional layers of insulation and screed and usually run at a fairly low temperature (35^o). This works best when the house is highly insulated and airtight, reducing the space heating requirement.

 

If you use a ASHP then in summer this can be run in reverse to cool your slab on warmer days. Given your sunny location I would ensure that solar PV is part of your design as it will be able to make a significant contribution to your power requirements in summer. I'd also make provision (really just ducting & services initially) for split air conditioning should overheating become problematic.

 

MVHR is very effective at delivering fresh air while minimising energy loss but given the intentional low airflow of these systems, it's not an effective means of moving heat (or coolth) around the house. That said, in a very efficient home (approaching passive standard) then it can act as a trim function.

 

Think also on external blinds for east & south facing windows as this prevents heat penetrating the house early in the day.

 

Our building (similar size to your proposed one) has a twin wall timber frame construction with the cavity insulated with pumped cellulose. This delivers great insulation but also has high decrement decay and good soundproofing properties. Your windows will also be key, triple glazing will deliver excellent soundproofing and tend to have the necessary seals and gaskets that help also.

 

Also important to remember that any external facade (brick, stone, render, timber cladding etc..) can be combined with any structural system (block, timber frame, ICF) and the various structural systems all have their own pros and cons wrt speed of construction etc and all tend to balance out cost wise - the structure is usually only 20% of the building cost.

 

I guess the big takeaway here is - design and build using the system and spec that gives you the house and performance you want - don't be confined to only what your builder friend is comfortable with and don't fall for the story that other systems are 'too expensive'. Do your research and understand all the pros and cons.

 

Good luck, you'll get lots of help here - between us we've probably used every type of build system and made every mistake there is to make

 

Great help thanks 

[7dayworker]

2 hours ago, JohnMo said:

+2, about friends, different rates of work and expectations, for a couple of weeks is ok, for months on end, could drive you up the wall.

 

Are you down sizing to a six bed house for retirement?

 

UFH is easy enough, it sits above the ground floor installation and in the screed.  Have a u value circa 0.1, this will limit downwards heat loss. 

 

You mentioned outer skin of building, how are you building the structure?

 

Light, big windows are great, but the downside can be over heating.  Even with big overhangs, the sun when it in the west and low can cause over heating, so watch for that.

 

We have a well sound proofed internal walls, but a door open circumvents all that.  So I would not get to hung up about it, if you have 70mm stud walls, use 25mm sound insulation job done.

 

All the things mentioned about airtightness, contractors in the main have no clue about airtightness, don't care, don't understand the issue, generally think you are daft wanting an airtight house.  

 

Bamboo, lots of weedkiller, one that attacks the roots

Yes annoyed that bamboo strayed from a neighbour. This builder just built his own home and is reliable ,but known to be expensive.

the structure will be block and brick , with render to add contrast.

[7dayworker]

1 hour ago, Bitpipe said:

We demolished and rebuilt. It removes all the risk and uncertainty related to the previous fabric and gives you the opportunity to build a modern, energy efficient and comfortable replacement home. If you get it right, your running costs will be minimal and it will be a very pleasant environment year round.

 

Airtightness and high levels of insulation are key, given you're in the south coast you'll need to focus more on managing summer overheating than winter heating.

 

Sadly a lot of the construction industry, architects included, are still stuck in the past and will design and build to a minimum building regs standard with minimum insulation in walls, trickle vents in the windows, radiators everywhere etc. You can do better so do your research now.

Thanks . I think the plan is to follow your tips and stuff I read and watch.  Underfloor heating and insulation 

[7dayworker]

1 hour ago, SteamyTea said:

Welcome.

If you choose your insulation type carefully, then it can help reduce noise transmission.  Same with glazing.

Just to make the distinction between energy use and technology type used clear, the building 'needs' an amount of thermal energy to keep it at the temperatures you like, regardless of how that energy is supplied.  So thermal modelling is important.

 

Now, you being a Doctor has reminded me of the 1990 Bootle By-election when the RLMP got more votes than the SDP, so to quote Scream Lord Such when asked if they would merge with the SDP, "We could use a good Doctor".  It is the same here.

 

I used to live in Lower Parkstone, we called it Upper Sandbanks.

Thanks . I can’t see a plan for thermal modelling, but will raise it . We had 2 meetings with the architect,the second just adjusting the interior .  He seems busy and not keen to explore …??

[7dayworker]

3 hours ago, ToughButterCup said:

Excellent. Could I now sound a cautionary note about friends working for you? ...You did ask ...

 

In this context, professional detachment is extremely difficult:  be the issue mate's rates, or employees drinking tea half the day or cash flow, or whatever, there's built-in stress. Every single build has at least one - often more - Oh FFS moment.  That's when professional detachment is a god send.

 

I'm not suggesting you find another builder, just a little nudge.

Thanks . The builder is not my friend but my daughter’s . So my idea was to aim at turnkey similar to his new build home . No mates rates . 

[Jilly]

17 minutes ago, 7dayworker said:

. The builder is not my friend but my daughter’s.

Could still be tricky. Most people try to get three quotes to compare, so you won't be able to do that. We used a friend for a project. We are no longer close... 

 

Speak to previous customers.

 

[SteamyTea]

36 minutes ago, 7dayworker said:

can’t see a plan for thermal modelling, but will raise it

It is something that has to be done sometime.

Many architects consider it someone else's problem, and most builders consider airtightness not in the least important, or a route to condensation. 

 

Don't fall into the trap that 'the professionals' actually know what they are talking about. Much of it is sales led.

[SimonD]

12 hours ago, 7dayworker said:

im just going to planning and would like

 

12 hours ago, 7dayworker said:

my queries are around light and sound proofing

 

12 hours ago, 7dayworker said:

the architect thinks a full brick exterior is the solution , but I’m not sure of the bulky impression that creates .

 

I would take a few steps back here to ask about the design process. I may have read this entirely wrong but from your questions something doesn't quite sit right with me. It doesn't seem like you've received a design service as that would normally entail the architect asking you what you like/don't like design wise and then going through an interative design process with you. This would involve discussions about exterior finish, as well as light and sound proofing, particularly if it's to reduce solar gain/over heating problems and your requirements as a client..

 

First I would dispense with the immediate technical discussion, go through a mutual design process which would naturally proceed to the technical details such as thermal performance, heating system and ventilation design etc.

 

39 minutes ago, 7dayworker said:

Thanks . I can’t see a plan for thermal modelling, but will raise it . We had 2 meetings with the architect,the second just adjusting the interior .  He seems busy and not keen to explore …??

 

Just read this. Doesn't sound good from a design or relationship perspective going forwards as you may well need to call on the architect a lot during the project, especially if there are issues with planning wanting amendments etc. I'd be talking to some alternative architects right now...

[7dayworker]

7 minutes ago, SimonD said:

 

 

 

I would take a few steps back here to ask about the design process. I may have read this entirely wrong but from your questions something doesn't quite sit right with me. It doesn't seem like you've received a design service as that would normally entail the architect asking you what you like/don't like design wise and then going through an interative design process with you. This would involve discussions about exterior finish, as well as light and sound proofing, particularly if it's to reduce solar gain/over heating problems and your requirements as a client..

 

First I would dispense with the immediate technical discussion, go through a mutual design process which would naturally proceed to the technical details such as thermal performance, heating system and ventilation design etc.

 

 

Just read this. Doesn't sound good from a design or relationship perspective going forwards as you may well need to call on the architect a lot during the project, especially if there are issues with planning wanting amendments etc. I'd be talking to some alternative architects right now...

Thanks Simon . I will raise your point about the mutual design process with my builder as he deals with the architect . The plans look okay now, after our input …this is really because we know the light and sound ,exposure etc as we lived here for decades. After the first tour , we re-configured the rooms and met up to discuss the kerb appeal and exterior , but with the builder who met the architect (junior) . The house is rectangular and divided into 4 beds on first floor and open plan with tv room , study, pantry , utility, cloaks garage etc The loft has 3 beds and bath storage etc .

 

The biggest issue was the exterior design as we wanted traditional rather than box design . Yesterday, we walked some expensive streets and took photos of similar fronts in different brick ,render etc. We will ask the builder to look at these on his return from ski trip next week.  He looks able and willing and relates well to the team.

 

This is the first stage , but so important and why I turned to people with experience.  If there is too much stress , I know my wife will back off and choose a bungalow ,if you can find one updated near here.

[7dayworker]

40 minutes ago, Jilly said:

Could still be tricky. Most people try to get three quotes to compare, so you won't be able to do that. We used a friend for a project. We are no longer close... 

 

Speak to previous customers.

 

Thanks Jilly . I will ask him about previous customers as I only see what is on his website. That is a good point . We are very trusting ,and  have lost out at times ..

[Wumpus]

For me, it’s unusual for your builder to lead the discussions with your architect. You are the client and things can get lost in translation at the very least. It may also result in something optimised for your builder and not you, and may put off any other builder competing for the business. Obviously your choice, but it does put a lot of trust and faith in your contractor.

 

Thermal performance and air tightness will probably not be a priority for either unless you make it so. There’s a decision to be made about what kind of house you want - highly insulated and Passivhaus-like, good, or whatever your builder decides.

 

One thing I found invaluable is to have a highly detailed schedule of works that defines what will be built, how and to what standards. If you want to have an MVHR working effectively, you might want to put in an air tightness standard to be achieved by the contractor, for example 3 ach for “just about good enough”, or perhaps 0.6 ach for Passive. Your architect can help to put this schedule of works together, but I would be cautious of having your contractor write it without independent expert input.

[JohnMo]

"I will raise your point about the mutual design process with my builder as he deals with the architect."

 

Think could end up a bag of worms. You say something to builder, his head interprets what you have asked, he does a sense check based on experience and his own expectations (which may not be same as yours or in same direction as your).  The architect is working in the builders interest not yours, your just someone being a pain in the background, although you ultimately pay the bills.

 

Personally I would have the architect work directly for you, so your options have to be heard.