Extension (slightly large...) and renovation in Cambridgeshire

[Tuppers]

Hi all,

 

Really happy to be part of the community having read a lot of things on here and finally at a point whereby I wanted to sign up, introduce myself, and what we (hopefully...) have planned, but a bit of backstory first! We live in Cambridgeshire and bought a 1930's semi detached house back in covid times which we're hoping to be our forever (or at least 20+ year) home for our family (2 adults, 2 kids). We're looking to do as much work ourselves as possible to keep costs down and have done a number of things previously such as full subfloor replacement, rewiring, ceiling replacement, bathroom install, etc. so have "some" knowledge and skills.

 

Due to various factors, we've taken a long time to get plans created. Our planning application was originally denied (we were caught out by the whole terracing effect side of things) and we've since gone through pre-planning with a revised set. From this consultation we're now updating plans in order to resubmit and are hopeful to get approval based on the outcome of the pre-planning meeting and report. I'll post plans once we've had them updated, but the scope we're hoping for is:

• Large single storey rear extension with vaulted ceiling (~7m x 7m) - open plan kitchen/dining/seating area with concealed prep kitchen area
• Ground floor side extension out to and following the line of the boundary (starts ~3m wide, opening out to about 3.5m at the back of the original house) from level with the bay window at the front of the house to the rear of the original house - garage at front, utility/bathroom behind it
• Side first floor extension, set back 200mm from the front of the existing house and 500mm from the side boundary, through to the rear of the existing house - bedroom and bathroom
• Full dormer loft conversion across original and new side extension, changing roof style from hip to gable - master bedroom, ensuite, dressing room/study
• Solar panels on pitched/flat roof (front is south facing)

 

Things we're not decided on but currently considering:

• Replacing existing timber suspended floor in original property for concrete slab with underfloor heating
• Ground source heat pump with boreholes (very much up for a good discussion on this!)
• Battery system connected to the solar panels (most likely will do)
• Externally insulating solid walls of original house

 

Hopefully this all sort of makes sense, and yes, I'm aware this is a huge amount of work! I've got lots of questions about things but am busy reading up on posts first of all so I don't ask any answered questions (where possible), but look forward to engaging with the community and hopefully giving back where I can too. Feel free to ask any questions if you have them!

 

Tuppers

[Mike]

Welcome to the forum!

 

Someone else is bound to say this if I don't so... from the extent of your works, you may be better off rebuilding. But either way you've come to the right place :)

 

 

[Mr Punter]

If you post some floor plans you could get some useful feedback on the layout.

 

For the floor, make sure you have minimum 150mm PIR or 250mm EPS if you have the room.  Allow 50-75mm for screed and 20mm for floor finish.

 

EWI can look a bit odd on a semi unless the junctions are well considered.

 

Ground source heat pumps are increasingly far more expensive and less popular than air source.  I think you would regret it.

 

You could do the solar panels and add batteries later if you have made provision for them.

[Tuppers]

58 minutes ago, Mike said:

Welcome to the forum!

 

Someone else is bound to say this if I don't so... from the extent of your works, you may be better off rebuilding. But either way you've come to the right place

 

 

Thanks for the welcome! The manner in which we're planning it means that there won't be major changes to the main fabric of the building, also in an effort to reduce costs. That's the "plan" anyway, whether or not it works out like we hope...!

[Tuppers]

34 minutes ago, Mr Punter said:

If you post some floor plans you could get some useful feedback on the layout.

 

For the floor, make sure you have minimum 150mm PIR or 250mm EPS if you have the room.  Allow 50-75mm for screed and 20mm for floor finish.

 

EWI can look a bit odd on a semi unless the junctions are well considered.

 

Ground source heat pumps are increasingly far more expensive and less popular than air source.  I think you would regret it.

 

You could do the solar panels and add batteries later if you have made provision for them.

 

So as it stands the pre-app plans we submitted look like the below, however there are changes which are still to be added which my post indicated. We've also got a rough plan of the kitchen layout as well which I've included as well

 

Pre-app plans

Kitchen plan:

 

 

[Tuppers]

44 minutes ago, Mr Punter said:

If you post some floor plans you could get some useful feedback on the layout.

 

For the floor, make sure you have minimum 150mm PIR or 250mm EPS if you have the room.  Allow 50-75mm for screed and 20mm for floor finish.

 

EWI can look a bit odd on a semi unless the junctions are well considered.

 

Ground source heat pumps are increasingly far more expensive and less popular than air source.  I think you would regret it.

 

You could do the solar panels and add batteries later if you have made provision for them.

 

We replaced the entire ground subfloor (asides from the concrete in the kitchen) so I know we've got a good 600mm+ to help retrofit the UFH in the main ground floor of the house, the kitchen (which will end up being a mix of rooms) will be a different story though...

 

On the EWI side of things, there are a lot of council houses on the street and they have all had it done together with solar/solartherm, so a lot look quite odd next to ex council houses that haven't had it, but it's a decision to be made in due course.

 

GSHP was the preference (mainly to save on having an ugly looking thing out the back/front of the house), however, my wife has just given the go ahead to look at ASHP instead! I now need to investigate more about placements/distances from cylinders etc. Idea would be a cylinder in the utility room.

 

I'm hoping to get solar and batteries installed at the same time on a deal of some description, but agreed, we'll get appropriate provisions in for them as I'm really keen to future proof ourselves where possible.

[Mr Punter]

The kitchen layout is not good.  Maybe get a design done.

 

The new cavity walls wrap around a fair bit of the existing which reduces the EWI a bit.

 

You need to make sure the left hand gutter and roof does not overhang the boundary.

 

That is a hell of a lot of work and a pain if you are living there.  Have you priced it?  If it works for you, get it done ASAP or the kids will have grown up before it is complete.

[Tuppers]

6 hours ago, Mr Punter said:

The kitchen layout is not good.  Maybe get a design done.

 

The new cavity walls wrap around a fair bit of the existing which reduces the EWI a bit.

 

You need to make sure the left hand gutter and roof does not overhang the boundary.

 

That is a hell of a lot of work and a pain if you are living there.  Have you priced it?  If it works for you, get it done ASAP or the kids will have grown up before it is complete.

 

Yep, it is a lot of work but we may choose to do it in stages. We got a rough price on the original rejected plan a while ago, but with the increase in prices of everything we're looking at doing as much ourselves as possible. We're in a perculiar position whereby we're not living in it, but a family member is, and they're comfortable with work going on whilst still being there (whilst safe to do so).

 

I'm keen to understand your comment and thoughts on the kitchen layout? It's not the best picture as it doesn't show clearly where everything is. Admittedly I've done it based on my wife's thoughts and felt that something was off about it, but couldn't quite work out why. We are planning on speaking to someone about it but I'd love to hear your thoughts in the meantime!