Conversion Heating and Services Questions Checklist

Note whether a boiler, hot water cylinder, tank or pump stands in the space, and photograph each one where it sits with its pipework.

Relocating any of these is a project in itself and it usually decides how a conversion is sequenced.

Moving a boiler, cylinder or anything connected to a fuel supply must be carried out by a suitably qualified professional.

Note whether the electricity, gas or water meter is located in this space, and where the supply appears to enter the building.

Meters belong to outside organisations with their own processes, which run alongside the building work rather than within it.

Anything involving a meter or an incoming supply must be arranged with the relevant provider and a suitably qualified professional.

Note where the consumer unit sits and whether it would end up inside the finished room, behind a finish, or somewhere awkward to reach.

It has to remain reachable, and its position sometimes constrains the layout more than anything else in the space.

List the appliances currently living in the space, including a washing machine, a freezer or a drier, and decide where each would go.

These appliances need supplies, drainage or ventilation wherever they land, and the receiving room is often already full.

Note any outside tap, garden socket or outdoor light fed from within the space, and write down whether you still want each of them.

These are easy to allow for while the work is going on and irritating to reinstate once everything is finished.

Find the main water stopcock and any isolation valves in the space, and note whether they would still be reachable afterwards.

Being unable to reach an isolation point in an emergency is a genuine consequence of a poorly planned conversion.

Write down what currently heats the house and how old you believe it to be, together with anything you know about its service history.

This is the starting point for any conversation about adding rooms, and the owner is the only source for the history.

Note which existing rooms already struggle to get warm, since those are the ones most affected by adding more demand.

Adding to a system that is already stretched at one end usually shows up first in the rooms furthest along.

Ask a qualified professional whether the existing arrangement can serve the additional space, and record the answer in their words.

This is exactly the kind of question owners answer for themselves optimistically and then regret.

Whether a heat source can serve additional space is a determination for a suitably qualified professional, never an assumption.

Write down whether the conversion would add a bath, shower or basin, and how that changes the number of people using hot water at once.

Hot water demand often turns on simultaneous use rather than the total number of outlets, and households can describe their own pattern.

Ask whether the converted space could be heated independently of the main system, and what the practical differences would be.

Sometimes a separate arrangement suits a detached or remote space better, and it is worth asking rather than assuming.

Decide in advance what you would do if you were told the existing arrangement cannot serve the new space, so the answer does not stall the project.

Owners who have thought about this respond calmly, and those who have not tend to make hurried decisions.

Describe the likely route from the existing system to the new space in terms of which rooms, floors and walls it would have to cross.

Routing determines the disruption, and describing it by rooms crossed is far more useful than guessing at distance.

Note which existing floors would have to be lifted to get supplies across, and what finish is on each of them.

Lifting an existing floor finish is often the largest piece of collateral damage in a conversion.

If the space is detached, ask what running supplies underground across the garden would involve and what would be dug up.

Buried services across a garden are their own piece of work and are very often treated as an afterthought.

Underground services, their depth and their protection must be specified by qualified people and confirmed against local requirements.

Note anything you already know to be buried between the house and a detached space, including drains, an old soakaway or a supply pipe.

Owners frequently hold the only knowledge of what a previous project buried in the garden.

Ask who is responsible for making good the walls, floors and finishes along the route, and get that agreed in writing.

Making good along a services route is a common gap between trades and a common source of dispute.

Consider what else could be run along the same route at the same time, including data, an outside tap or a spare conduit.

The route is only open once, and adding something to it then is far easier than reopening it later.

Write down when the converted room would actually be occupied, and whether that matches when the rest of the house is heated.

A room used at different times from the rest of the house is the classic argument for separate control.

Note where the existing thermostat or control sits, and consider whether it would represent the converted space at all.

A control in a hallway cannot sense a converted garage, which is why such rooms often feel wrong however the system is set.

Ask whether the new space can be controlled separately from the rest of the house, and what that would involve here.

Zoning is much easier to build in while pipes and cables are being run than to retrofit afterwards.

Mark on a rough plan where you would accept a radiator or emitter in the new room, given the furniture and openings you want.

Emitter position is often decided on site by whoever is holding the pipe unless the owner has already said something.

Ask whether heating within the floor is a realistic option in this space, and what depth and preparation it would need.

In a conversion this depends entirely on the existing floor, so it is a question for the property rather than a preference.

Whether any floor-based heating suits your existing construction must be established by a suitably qualified professional on site.

Consider how the space is likely to behave in warm weather, particularly if it faces the sun or has glazing overhead.

Conversions are frequently designed against cold and then turn out to be uncomfortable in the opposite direction.

Walk outside and note where existing drains, gullies, inspection covers and soil pipes are, photographing each one.

Where drainage already exists is what usually decides whether a wet room in a conversion is straightforward or difficult.

Note whether the proposed fixture would sit above or below the level of the nearest existing drainage, and raise that as a question.

A fixture below the drain line is a different proposition entirely, and owners can spot the risk from what they can see.

How drainage falls and where a connection can be made must be determined by a suitably qualified professional and confirmed locally.

Ask how a shower room or utility in the converted space would be ventilated, and where the extract would discharge.

Extract has to go somewhere, and its route and outlet position affect both the design and the neighbours.

Ventilation provision for a wet room is determined against the relevant local requirements by a qualified professional.

Note how the existing taps and showers perform, since a new outlet at the end of the run inherits whatever the system already does.

Owners can describe existing performance accurately, and it is genuinely useful information.

Ask what any equipment needed to make drainage work would sound like, and where it would be placed relative to living space.

Equipment that solves a drainage problem sometimes creates a noise problem, and that trade should be stated up front.

Consider what sits directly below or beside the proposed wet area, and note what a leak would reach if one ever happened.

This influences where a fixture is placed and what precautions are worth discussing, particularly above a habitable room.

Note what electrical points already exist in the space, including sockets, lights and any supply to a door mechanism.

What exists tells a professional something about how the space was originally supplied and what may be reusable.

Write down what would actually be plugged in or fixed in the new room, including anything with a heavy demand such as an oven or a heater.

The demand list is what a qualified person needs, and only the household can produce it honestly.

If the space is detached, ask what supplying it separately would involve and how that supply would be protected and isolated.

A detached space is a different arrangement from a room in the house and needs its own conversation.

Electrical supply, protection and isolation must be specified and carried out by a suitably qualified professional.

Mark on a rough plan where you want to switch lights from, considering both entrances to the space if it has two.

Switching positions are easy to settle on paper and a lasting irritation once they are wrong.

Ask what alarm or detection provision would apply once the space becomes habitable, and treat it as a question for professionals.

Once a space counts as habitable, detection provision tends to be looked at differently, and the answer is not the same everywhere.

Alarm and detection provision is determined against the relevant local requirements; confirm it with the responsible body and a qualified professional.

Note how well the internet signal reaches the space today, and decide whether a cable should be run while other work is going on.

A converted space used for work often has poor signal, and the moment to deal with it is while routes are open.

Ask where every valve, isolator and control would end up, and confirm that each one could still be reached without dismantling anything.

Access panels are easy to include in advance and destructive to create afterwards.

Decide where you are willing to have access panels visible in the finished room, and say so rather than leaving it to be resolved on site.

Access has to be somewhere, and owners who state a preference get a better result than those who do not.

If the space would be used independently, ask what separate metering or sub-metering would involve and who arranges it.

This comes up with annexes and workspaces and it involves outside organisations rather than the builder.

Metering arrangements are handled by the relevant provider and may involve other requirements; confirm them directly rather than assuming.

Ask what written record you would receive of the services work, and agree at the outset that you expect one.

Documentation of what was put in and where is what makes the next piece of work possible without opening walls.

Agree that pipes and cables would be photographed before they are covered, and that you will be given those photographs.

A set of photographs taken before closing up is the single most useful record an owner can hold for the future.

Write down who would be responsible for servicing each item once the work is complete, and how you would arrange it.

New equipment brings ongoing obligations that are easy to overlook while attention is on the building work.