Second Boiler in Outbuilding. LPG. Pipework?

Lumphammer2

We have an LPG boiler (and hob) in the house, supplied from an underground bulk tank 30m away in the garden.  We have an outbuilding which is used as an office which is heated by electric panel heaters.

We are considering alternatives to the electric heating.  It doesn't appear practical to extend the existing house CH system to the outbuilding, which is 10m away from
the house, (and 40m from the bulk tank) so we are thinking about getting a second boiler and CH system.

I am unsure whether the existing pipework from the house could be extended to supply the outbuilding or whether a new supply could be taken from the tank.  Whichever,
are there any other issues or considerations I should take into account.  My LPG supplier will provide a quote for new pipework - and I suppose they will be in a monopoly situation - at least until my contract is over?

Any thoughts?  Thanks in advance.

Ectophile

Do you need a second gas boiler, or just a gas fire in the outbuilding?

If you take the LPG supply from the house, does the LPG supplier need to be involved?  Can't a Gas Safe registered plumber do all the work?

Mister_G

Indeed.  Your LPG supplier may have provided the external pipework from the tank to the house, but anything after their shut off valve is yours.  An RGI (Gas Safe) can certainly tee into the supply after this and route a gas pipe to your outbuilding.

Rodders53

First INSULATE and draught-proof the outbuilding to within an inch of its life.  That will reduce heat loss and (solar gain) perhaps.
Cost out the alternatives for heating the building:
1)  Current panel heater: how much heat input is needed in kWh used per day/week/month/annually? Cost of your electricity for that. Presumably you have heating controls (simple timer or smart switch to turn on/off from the house so it's 'ready to use') for it.

2) LPG Gas Fire:  Cost to supply and install.  Can it be remote or timer controlled to switch on/off as wanted? Cost of gas based on fire efficiency and your LPG price to supply the same kWh as 1)  How long to pay back install with energy cost savings?

3) LPG Boiler and radiator(s):  Cost to supply and install, including controls.  Cost of gas again (with boiler efficiency)?  How long to pay back?

4) Cost out a small air to air heat pump, with installation, to save electricity while heating (but maybe cost some to provide cooling in summer).  

You may find that the payback might never happen in a sensible timescale.

Lumphammer2

The outbuilding is about 3.5m x 8m and contains a small hallway, a small lobby and off from that one large room (office) and a small shower room.  While heating is the main issue, having hot water would be very useful in the building - so we hadn't really considered just a gas fire.

British Gas came out to discuss a boiler in the outbuilding (we wouldn't use them - £££) and suggested that the LPG supplier would need to supply gas to the building.  I wasn't sure if the existing supply could be tapped or if it needed a complete new pipe from the tank.

It seems the polypipe can be only 200mm deep if covered with a slab. 

Lumphammer2

Posted that before seeing the other replies.

Thanks all of you.

If after the shut-off valve is ours, I presume enough gas pressure for appliances discussed?

Currently have panel heaters on timers/stats.  Have considered but not bothered with 'remote switching' from house.  Will definitely consider LPG gas fire.

I am ignorant of air to air heat pumps but will gen up.

A complicating factor is that it may be that the building could be used as a self-contained unit/let at some point in the 
future and while I don't mind putting up with less than CH level heating, others may not!