Hello from Berkshire

[kxi]

Hello all

 

We recently got planning for a barn conversion in Berkshire, to be our family home. We've been working on the design & permissions for a couple of years, during which time this forum has been invaluable.

 

The barn is on a small arable farm at the edge of a cluster of in-use agricultural buildings. It was originally built as a cowshed in the mid 60s, brick on 3 sides and open at the south face, with a mono-pitch fibre cement roof. See image below.

 

The open south face looks into large concrete & fibre cement barns about 5m away (i.e. not ideal). The north side looks out to trees then fields beyond.

 

We have class Q permitted development to partially convert the barn to a dwelling. A subsequent full planning application to make changes to the eaves height and roof pitch was rejected and we didn't appeal. The idea is to add a first floor to the existing barn and then the majority of the house be on this first floor, with most of the ground floor remaining in agricultural use. This arrangement is to maximise the available space, gain more south light into the house (as the large sheds to the south block everything at ground floor level), and because we like living off the ground.

We're also nicking off the top west corner of the existing shed to make a first-floor terrace at the west end of the house.

 

Diagrams below show model photos and a comparison with the existing barn.

 

The aim is for very good insulation and airtightness, but I don't think we will go for full passivhaus due to the poor form factor and that we want a lot of north-facing glazing. Our architect designed & built their own passivhaus a few years ago, so is familiar with it.

 

The long rooflight running east-west (see model3.png) is to allow light into what might otherwise be a dark central corridor, and allow borrowed light into the north facing rooms via internal clerestory windows off the corridor. The rooflight is north-facing (though on a shallow pitch roof) so less of an overheating risk. There was PHPP modelling of an earlier iteration and the overheating was acceptable, but we'll re-visit this to check.

 

We had originally assumed twin-wall timber frame + cellulose for the build method. However, with some changes in requirements, we are re-assessing this. Keen to get people's view on the alternatives that we'll be considering. TBC.
 

[Russell griffiths]

Ooooooh I like that, do you use the other barns, could they fall down????

[Bitpipe]

Welcome - I'm east Berks.

 

Very impressive and ambitious!

 

 

[jack]

Welcome to Buildhub - looks amazing!

[newhome]

Welcome! Looks like a great project. 

[vivienz]

What a terrific project. Keep us posted. Images and photos are very welcome.

[kxi]

Thanks everyone

 

@Russell griffiths   The other barns on the farm are still in agricultural use, as was this one, but we're shuffling things around to make room, though since much of the ground floor can stay in farm use it shouldn't be a huge change (but the piles of old wood will have to go). The other barns are a mix of 1940s (allegedly built by/for Italian prisoners of war) and 1960s, and they are all in fairly good shape. Though the 60s ones have a bit of concrete spalling on a couple of pillars which should be attended to. In terms of future non-agricultural use, we'll have to see once we've got this little project out of the way.... there are various planning limitations. I note your question about insulated panels for the roof - this is something I've been looking at recently and will post thoughts and questions later, but it's definitely a route we're considering. Overall we want to keep an agricultural flavour and we need to find a solution that is as thin as we can make it (without going aerogel which isn't remotely feasible for ~350m2 of roof).

 

@Bitpipe East also. I may need to ask for some local knowledge advice at some point if that's ok.

 

Worth noting our architect doing these cardboard models really helped us grasp the physicality of different designs in a way that even sketchup modelling didn't. I know an architect isn't the right way to go for all projects, but I think it's definitely worth doing a real model, especially to help communicate to people who are less immersed in the design - family, planners, neighbours, etc.

 

 

[newhome]

21 minutes ago, kxi said:

but I think it's definitely worth doing a real model, especially to help communicate to people who are less immersed in the design - family, planners, neighbours, etc.

 

@JSHarris made a model of his house complete with a woman in a bikini standing in the shower to help his wife visualise the size of the shower . 

 

 

[Jeremy Harris]

5 minutes ago, newhome said:

 

@JSHarris made a model of his house complete with a woman in a bikini standing in the shower to help his wife visualise the size of the shower . 

 

 

 

 

I did indeed!  I made around 5 or 6 models of the house at a large scale (1:50), just so that my wife could get a better feel for the spaces inside.  There are photos of the final design, plus the smaller scale model of the house on the plot (to help with planning consent, which it did) in this post:

 

 

 

[kxi]

@newhome   @JSHarris  I'm now curious as to what I might find inside our own models.

 

There are a couple of aspects of the design that I think it would be handy to model life-size, in particular, a sloping roof height issue. Perhaps using some sheets, drawing pins and a wooden frame.

[Jeremy Harris]

I made our large scale (1:50) models by printing off 2D drawings and glueing them to foam board (available from artists suppliers, some stationary suppliers) using spray mount.  Foam board is dead easy to cut accurately and quickly using a sharp craft knife and a steel rule.  I used PVA glue with pins to hold the parts together whilst the glue dried.  For internal walls I used LitePly (available from model shops) which is also easy to cut with a sharp craft knife, and used the same technique of using spray mount to glue the printed plans to the LitePly.

 

I added an extra layer of LitePly to the external foam board to give a scale wall thickness, but LitePly on its own is close to scale thickness for internal walls.  I printed some textured paper for the roofing and made the model so that the roof and first floor could be lifted out to show the areas beneath.  Using 1:50 as a scale is useful, because you can buy model people at the same scale from model railway shops, that help to give a sense of scale to the model.

[ProDave]

Interesting project. but seeing how it sits amongst the other barns I have to question if this was the best one of the barns to convert?  Would one of the others not have given a better outlook?

 

At least if the ground floor is staying partly as agricultural use, you can continue keeping the Series 3 under cover.

[ToughButterCup]

Welcome.   I'm with Dave on this one.

My major modelling concern is the serious issue of how the Landies are going to fare. Will they be forced out into the harsh, wet cold British winter? I do hope you'll have a risk assessment done for that. Series 3s are delicate beasts.

Well, mIne was.

[kxi]

@ProDave The barns to the south are unfortunate, but this barn has by far the best view (to the north) and all the other barns are too small to be used on their own so would require stringing together in an impractical way. Since it's green belt, extensions are limited by planning (we did try). The barns to the south probably had a design life of 50 years and are 55 years old, so it's likely the house will live to see a change to the south. The way we've looked at it is that most houses don't have views on all 4 sides, and 3/4 isn't bad.

 

+ @recoveringacademic  I see you are both admiring our series 3 sculpture. I have access to a conservator who can advise how we can preserve this for future generations.

Having a ground floor that can fit the newer models (+ necessary fire-proofing to the ceiling) is one of the big factors in the build method choice. 

[kxi]

@vivienz One of the designs that we didn't go for, and turns out wouldn't have been allowed by planners anyway as involved a bulk increase, was a thin full-length clerestory for summer-shaded south light, which I think would have looked great (if you could fly).

[Ferdinand]

Welcome to the forum. An exciting project.

 

Could you do something interesting with the Barn opposite, like paint it in camouflage or a mural of the landscape behind, or put some mirror-type strips on it with climbers in between? Or even something that will break up the shape?

 

Lots of possibilities, perhaps also using lighting from your side.

 

I think I would consider something to break up the monolithic block of ugly, and also something to make people coming in look beyond the wall and imagine that it is not there.

 

This is interesting - put a fence in front that reads like a garden then other side, then a mirror reflecting your side to pretend it is there. You could make it look like another house, or the landscape beyond the end of the alley beyond your house for visitors looking at an acute angle, who then see an image of the side of your house as they walk forward.

 

 

There are probably lots of good ideas you can borrow from tight urban designs, or other places, for your outside environment too. Here's another I like.

 

 

>The long rooflight running east-west (see model3.png) is to allow light into what might otherwise be a dark central corridor, and allow borrowed light into the north facing rooms via internal clerestory windows off the corridor. 

 

Grand Designs last week had one of those that worked spectacularly well by being aligned carefully with the internal spaces of the room.

 

F

Edited September 30, 2018 by Ferdinand

[Ferdinand]

 

On the design - what is your plot shape.

 

Is there any scope for inside/outside living (eg Franch Doors) on the more attractive North side? I do not see that in the model, or perhaps  I missed it.

 

Ferdinand

 

Edited September 30, 2018 by Ferdinand

[kxi]

@Ferdinand Regarding the opposite walls, there's definitely some thinking to do here, but I'd mentally put it in a 'once we are finished' box. One idea was to add climbing plants, though the snag is they would be very shaded. This might be partly mitigated by cladding the house south face with stainless steel to reflect light from our south face onto the opposing side. This might not be effective or desirable though. Also the shed walls are made of white & blue asbestos fibre-cement, so I would not want anyone having to interact with them (e.g. for plant pruning), as any contact with the surface could in theory release fibres. The continuing presence of so many of these ageing, potentially lethal panels is something to be reviewed, but it would be a major undertaking to replace them.

 

"Grand Designs last week had one of those that worked spectacularly well by being aligned carefully with the internal spaces of the room."

Aha thanks, I'll take a look. It means the north rooms get light from two aspects, which is nice. How to operate the blinds/curtains over the bedroom ones is a slight snag but i'm sure can be solved.

 

"Is there any scope for inside/outside living (eg Franch Doors) on the more attractive North side? I do not see that in the model, or perhaps  I missed it."

On the west end there is a first floor terrace within the original walls (see 3rd model image) with large doors/windows into the main living area. This terrace looks out over the future garden & trees to the north, then the farmyard & other buildings to the west and south. These last are perhaps not everyone's idea of a good view, but it does get the sun & sunset and various birds like wheeling around the yard at certain times of the day. A north terrace would certainly get a better view, but is currently a no-go from a planning POV as it extends the existing footprint. It would also be shaded all the time as it's north facing (but that might be fine). A deck at the east end also would have a nice view and get the morning sun, but again not allowed under current planning regulations.

[Ferdinand]

On 29/09/2018 at 19:51, kxi said:

+ @recoveringacademic  I see you are both admiring our series 3 sculpture. I have access to a conservator who can advise how we can preserve this for future generations.

 

Wouldn't that be to spray with gold paint and bequeathe to Blue Peter as an example of excellence !

 

11 hours ago, kxi said:

"Is there any scope for inside/outside living (eg Franch Doors) on the more attractive North side? I do not see that in the model, or perhaps  I missed it."

On the west end there is a first floor terrace within the original walls (see 3rd model image) with large doors/windows into the main living area. This terrace looks out over the future garden & trees to the north, then the farmyard & other buildings to the west and south. These last are perhaps not everyone's idea of a good view, but it does get the sun & sunset and various birds like wheeling around the yard at certain times of the day. A north terrace would certainly get a better view, but is currently a no-go from a planning POV as it extends the existing footprint. It would also be shaded all the time as it's north facing (but that might be fine). A deck at the east end also would have a nice view and get the morning sun, but again not allowed under current planning regulations.

 

I was asking more about ground level, as marked, which I hope is part of the plot for this conversion (even if you own the whole farm) - if not boundary disputes may rear their heads in a generation.

 

 

I think that I can't comment more without knowing more, which it might not be suitable to post.

 

And then there are the intricacies of Part Q ?, which I will avoid:

 

Quote

A little learning is a dangerous thing;
drink deep, or taste not the Pierian spring:
there shallow draughts intoxicate the brain,
and drinking largely sobers us again.” 

 

F

 

Edited October 1, 2018 by Ferdinand

[kxi]

@Ferdinand yes that marked part is part of the plot, as well as another garden area to the east, also a decent curtilage around the whole building to allow for maintenance. Various covenants in place with the farm for access, services, etc. The woodland 'just out of shot' to the left of that model picture is under a long-term woodland management grant, and the whole area is green belt, so in the event of everything changing hands in years to come, the new owners shouldn't have to worry about their north view being onto an abattoir.

 

Class Q has been a bit tricky, but on a firmer footing with the recent updates about structure. Martin Goodall's blog has been essential. The planners are (now) happy with the design, and I think we've got a good relationship with the planning dept. Further amendments to include stainless steel cladding might be a step too far though.

 

If it's ever of interest to anyone, the GPDO does explicitly allow making design amendments to a previous class Q agricultural conversion PD, though councils may not initially know this is possible.

[kxi]

After much consideration, the build method we'll be using for the conversion is 'big shed'.

 

In that we'll be:

- Adding a new steel frame internal to the existing walls

- Which supports a new precast concrete plank first floor

- Then wrapping the roof, new walls, and potentially the underside of the new first floor in Kingspan KS1000rw insulated panels - 150mm quadcore. Bearing in mind the house is mainly single storey up in the air

- The panels fixed onto timber purlins for the roof, and off metal inline purlins for the walls

- Internally, the external wall panels & purlins hidden by PB/fermacell board covering the 'cavity', also board between the ceiling timber purlins to cover the underside of the roof panels 

 

Why this?

Naively, it seems like a simple & relatively cheap way to achieve a high-insulation (0.12U), thermal bridge free, airtight shell. Though the idea came about from trying to think of the thinnest roof possible without use of exotics like areogel (which for a 360m2 roof was out of the question) since we are very height constrained on the north side. Decrement delay issue noted. @scottishjohn

 

We also wanted a highly fire resistant first floor (hence the concrete) with large spans, due to the ground floor space underneath being agricultural use. This leads to a steel frame, which the kingspan panels go with. Frame & panels can then be constructed as a single package.

 

In terms of precedent, we have heard of a couple of similar residential examples, and I expect more will appear due to Class Q permitted development, and obviously there are lots of offices & workshops that use this approach, often as part of bigger sheds.

 

Various issues to work through, but making progress. For example we've found the north-south steel roof beams are thick enough to have 100mm holes cut to allow radial MVHR ducting, which gets it out of the way.