Building a "stealth bungalow"

[adam2]

Friends are considering erecting a large outbuilding on land that they own.
For use as a store and workshop and stable.
There is no intention to illegally use this structure as living accommodation whilst times are normal, but it might be so used after any serious emergency.

A simple and durable structure is required.
Built of concrete blocks, faced with brick.
Solid concrete floor.
Slate roof.
Small windows, fitted with steel shutters.
Toilet and shower.
Mains electricity.

My main concern is heating, a chimney for a stove would perhaps make it look too like a home. With no chimney, heating is restricted to electricity or LPG, both are expensive and unlikely to be available after any serious emergency.
A toilet and shower and basic cooking facility can be justified as being for the use of farm workers.

[Little John]

All they need for a chimney is a metal tubular flue going out of a hole in the wall and then extending up the side of the building. If they are not intending to use it at the moment, they could fit the stove and have the flue on hand which they could then fit at short notice should the need arise. They could even have the majority of the flue extending up the interior of the wall in order to capture any residual heat in it and only have it going outside at the last foot or so. That being the case, the majority of the flue could be fitted in place now.

Additionally, if the cover story for this setup is that it is for farm-workers, I would have thought a stove and chimney could be cited as being necessary to keep farm-workers warm when they come in after are working outside in the winter.

[ReserveGrowthRulz]

Friends are considering erecting a large outbuilding on land that they own.
For use as a store and workshop and stable.
There is no intention to illegally use this structure as living accommodation whilst times are normal, but it might be so used after any serious emergency.

Doom bunkers in England!! And here I thought only Americans did that kind of end of world stuff!

[kenneal - lagger]

Facing an agricultural building with brick will immediately ring alarm bells in the planning fraternity whereas a block or rendered building will not. If it was built as a standard agricultural storage building with a corner walled off with a stove in it as a "mess room" with loo and shower that would not ring too many alarms.

If a standard agricultural building was erected with an insulated roof and insulation was placed on the outside of the walls and rendered ensuring that the wall insulation joins up with the roof insulation that would give a high mass insulated structure which wouldn't raise too many eyebrows. It will be best to build the standard building first, get it passed by Building Control and then add any bits to make it more habitable as Building Control will report any "suspicious" activities to planning.

They would also have to be careful with window placement as if it looks too much like a future house they will again face questions and possibly enforcement action to take the building down.

[vtsnowedin]

If you put in for an ugly corrugated metal siding some official on a power trip will insist on brick facing to make it match in with the proper view of the English countryside.

[kenneal - lagger]

Corrugated metal or cement roof more likely with black stained wood boarding or concrete block or panel for the walls, VT.

[adam2]

The intention, whilst times are normal, is that farm staff will use part of the new building as a mess room, foul weather shelter, tool and equipment store and changing room.
There will be a basic workshop for minor repairs to farm machinery, implements and vehicles.
A forge for blacksmiths work is to be included, and is expected to be well used even whilst times are normal.

The other half of the building will be for landlords/employers storage and staff wont normally have access to that area, though nothing conspicuous, unusual or controversial will be stored.


Looks like brick facing might not be such a good idea. Probably concrete blocks in that case.

The proposed building will have 3 phase mains electricity, water and drainage.
I will do the electric wiring, which will be more or less standard but designed for future connection to 12 or 24 volts instead of mains.

Lighting circuits on 6 amp MCBs in line with normal practice, but wired in 2.5mm cable. Nothing but standard B22 lamp holders to be connected to lighting circuits.
Socket outlets to be on 20 amp radial circuits but wired in 6mm cable.
Cooker, shower, and water heater circuits all to be wired in one size larger cable than the norm, for future re-use.

Grid tied PV proposed, with a view to re-purposing the modules for battery charging after any serious emergency.
One fast EV charger.
Space for charging 4 electric quad bikes, or slow charging extra EVs.

[clv101]

Are B22 still the best bet? Seems to be more choices in ES.

[vtsnowedin]

Seems like an interesting project. I only suggested the brick facing to match the other buildings in the area to deflect attention. Whatever keeps the local officials and public appeased will serve.
I can't think why you would need three phase power but of course your voltages are different then my US experience so I'm missing something. Do you need three phase to be able to grid tie the PV.?

[adam2]

If the electrical demand is significant then three phase is preferred.
Single phase in the UK is almost always 2 wire, 240 volts.
Single phase service is usually restricted to 100 amps, or about 24Kw.
Three phase service "from passing main" i.e. connected to an existing main is usually available up to 200 amps or about 144Kw.
A dedicated cable from an existing substation will allow up to about 400 amps.
Beyond that may require a new substation on land supplied by the customer.

In this case three phase is wanted for several reasons.
1) large arc welder may be needed, these often need a 400 volt supply, between any two phases.
2) possible future need for ultra fast EV chargers, or multiple fast chargers.
3) grid tied PV is allowed on single phase services, but three times as much is allowed on a three phase service.

A single phase 100 amp service would have been marginal.
Electric shower-----40 amps
EV charger----------30 amps
Electric cooker------20 amps
Water heater--------10 amps
Could reasonably be used at the same time, add a space heater or two and a washing machine, and kettle and it might end badly.

Three phase will allow for a second shower, and other large loads.

[vtsnowedin]

I stand educated. Carry on.

[kenneal - lagger]

It might be all well and good to plan for "more" in the future but the lesson to be learned from most of our discussion and the references there from is that the future will be less than the past not more. All that kit might have a limited use but if it can't be supplied from within the farm most of it has a very limited future.

[kenneal - lagger]

With the uses that you propose your client could expect no problems from planning if it was to be proposed as a BREEAM Excellent workshop, mess, and agriculture storage building provided they can show the agricultural justification for it and it is built in the modern agricultural vernacular for the area be that concrete block or timber cladding with corrugated roof.

[adam2]

Other agricultural buildings in the area are built of concrete blocks with corrugated metal roofs. The proposed new structure will therefore be similar.
Corrugated metal walls wont find favour as are vulnerable to gunfire.

Whilst times are normal, the facilities will be regularly used by the staff of a large farm.
In case of emergency, farm staff or relatives could live there.

A recent inspection by TPTB expressed dissatisfaction with the present inadequate staff facilities.

The new building will incorporate a large workshop with roller shutter door giving access to the outside.
A staff mess room able to easily accommodate 8 persons for meals and breaks. Fridge/freezer, kettle, microwave, double sink electric cooker, LPG cooker, LPG lights.
A changing room with clothing lockers etc for at least 8 persons, benches, coat hooks.
Of the changing room, 2 showers, 2 WCs, hand washing facilities.

Between the mess room and the changing room will be a ventilated laundry area with washing machines and tumble dryers.

A large secure chemicals store will be part of the building, but with only external access.

Secure tool store. Gun cupboard. Farm managers office. LPG store will be part of the building but with only external access.
Another three small rooms with only external access are reserved for future use as a generator room, battery room, composting toilet, or extra fuel storage.
Six general store rooms, potential future bedrooms. No beds or bedding to be stored on site, as that rather gives the game away. No intention for anyone to live there whilst times are normal.

The building will be divided into 2 zones, with the higher fire risk areas separated by a very substantial wall that will continue up to the roof line.

[kenneal - lagger]

.... Corrugated metal walls wont find favour as are vulnerable to gunfire.......

!!!

I know you live out West, Adam, but I didn't know it was that wild!!