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What an older building will accept, and who gets to say so
Comfort in an old house is rarely limited by equipment. It is limited by route, by fabric and by permission — and the third of those is the one that gets discovered last and costs the most to have got wrong.
Permission, then fabric, then equipment
The usual sequence is the reverse. Somebody chooses a system, a price is agreed, and then it turns out the outdoor unit cannot go where the drawing assumed — because of a rule, a neighbour, a shared wall or a clearance the manufacturer requires. At that point everything is expensive: the pipe run doubles, the crane becomes necessary, or the whole thing is refused.
Doing it the other way costs an afternoon. Establish where a unit may stand and what may cross a wall. Then look at what the building is made of, because a house with no insulation and single glazing needs a different machine from the same house after those are dealt with. Only then choose equipment.
So: what kind of building is it, and who else has a say?
What the building is, and who decides
Nothing is sent anywhere and nothing is recorded. This is what we would ask you on the telephone.
Associations and boards routinely govern four things that decide this job entirely: where an outdoor unit may stand, whether anything may be fixed to or penetrate a common wall, roof or slab, what may be visible from common areas or the street, and what noise is acceptable at a boundary. Some also require a licensed contractor with particular insurance, and a few require the work to be inspected.
Why this matters more than it sounds. Equipment installed on common property without approval can be ordered removed, and the cost of removal and of making good usually falls on the owner rather than on the contractor who fitted it. We have no way of protecting you from that, and neither has anybody else.
So our position is simple, and it costs us work: we will not fix equipment to common property, penetrate a shared wall, roof or slab, or run a line set across common area without the association’s written approval — whoever is paying, and however confident anybody is that it will be fine. A contractor who agrees to do it anyway is handing you a risk they will not be carrying.
What to ask for, in this order: the governing documents or house rules covering alterations and exterior equipment; whether an application is needed and what it must contain — usually a location, a drawing, the equipment’s published sound level and sometimes a screening detail; and how long a decision takes. We will supply the technical parts of that application at no charge, because it is faster for everyone. We will not lodge it for you or attend the meeting.
Ductless, almost always — and the roof space is the reason
A Craftsman bungalow typically has a low-pitched roof with very little usable space above the ceiling, which is exactly where a ducted system needs to live. What space there is tends to be shallow at the eaves, which is where the runs to the outside rooms would have to go. Forcing ducts into it produces long, kinked, badly insulated runs in a space that reaches an enormous temperature in August, and the result disappoints.
What we would do: one outdoor unit and heads in the rooms that genuinely need them — usually two or three, rarely one per room. Mounted high, ideally on an interior wall so the line set has a straightforward route down to a side elevation.
Two details that matter in these houses: a picture rail and plate rail give you a natural line to mount above rather than across, which makes the unit look deliberate instead of stuck on; and lath-and-plaster walls need care when they are cored, so ask who will be making good and see their work.
And the fabric first, if you can afford the order: insulation in that shallow roof space and weatherstripping at the original windows will reduce the equipment you need, and both are cheaper than the capacity they save.
The walls are an asset. Treat the route as the constraint.
Thick masonry or heavy stucco walls give these houses real thermal mass, which is why they often stay tolerable well into an afternoon and then stay warm well into the evening. That changes what you are solving for: you are usually managing the late-day heat rather than the peak.
What we would do: ductless, sized modestly, in the rooms used at the end of the day. An oversized machine in a house with mass is a poor match — it satisfies quickly, stops, and never dries the air out.
The route is the real work. Coring a thick wall is a different job from coring a stud wall: it is slower, it wants the right tool, and it wants somebody who has done it on a house of that construction before. Ask. And ask where the line set will run on the outside, because on these houses a badly placed cover is visible from the street for the rest of the building’s life.
What we would not do: cut a route through a decorative feature, a tiled surround or an original arch to save pipe. There is nearly always another way and it is nearly always worth the extra metre.
You may have a duct route already — but do not assume the ducts are reusable
A post-war house with a gravity furnace often has a genuine distribution route: large ducts, usually in a crawl space or a shallow attic, laid out when the system worked by warm air rising rather than by a fan. That route is worth having. The ducts themselves frequently are not: they were sized for a completely different method, they are often the wrong shape and size for a modern blower, and they may be in poor condition after seventy years.
What we would do: survey the route before pricing anything, and measure what it can actually carry. Some of these systems can be reused with new runs in the same path, which is the cheapest good outcome available in this kind of house. Some cannot, and it is better to know that in week one.
One thing to raise before any duct work starts. Insulating materials used on heating systems of that era commonly contained asbestos, particularly on duct joints, around the furnace and on pipe insulation. We do not test for it and we do not remove it. Before anybody disturbs a system of that age, have it assessed by a qualified inspector; if it is present, removal is a licensed specialty and a different trade entirely. Any contractor who offers to rip it out as part of the job is one to decline.
Establish what is yours before you establish what you want
In a building from the twenties or thirties, the boundary between your flat and the building is rarely where people assume. Exterior walls, the roof, light wells, the slab and often the window openings are commonly common property, and heating may be a building-wide system you do not control at all. All of that decides the job before any technical question is reached.
What we would do: find out what you are allowed to alter, then work inwards. Where an outdoor unit is genuinely not possible, there are honest options — a through-wall unit if the wall is yours, a portable done properly, or simply improving what the building already provides, which in a steam or hydronic building is often a matter of valves and balancing rather than of new equipment.
Where the building has central heating you cannot control: the useful work is usually at your end — a radiator valve that actually closes, a working thermostatic head, and stopping draughts at the windows. It is unglamorous and it is often the difference.
And the noise question is real here. A unit in a light well or on a shared wall is heard by several households. Get the published sound figure for anything proposed and take it seriously before a neighbour does.
Find out what the last remodel actually did before adding to it
A house that has been remodelled once is the most variable case on this list, because somebody has already made decisions you are now inheriting. Sometimes that is a gift — a proper duct route, a decent panel, a system sized against a real calculation. Frequently it is not: a system sized for the house before the extension, a return that was never enlarged, a zone added without rebalancing the rest, or a room that was added with no provision at all.
What we would do: measure before adding. Static pressure, airflow at every register, return capacity, and a load calculation against the house as it is now rather than as it was. Half the complaints in remodelled houses are a distribution problem created by the remodel rather than an equipment shortfall.
Ask for the paperwork from the last job. Permits, the calculation if one exists, and the equipment list. It is worth an email to the previous owner, and it occasionally saves a survey.
And be careful of matching. If part of the house works well and part does not, the instinct is to extend the system that works. Whether there is any spare capacity or airflow to extend is a measurement, not an assumption.
About bungalows specifically
Ask to be shown the roof space before anybody quotes ducted. If the person quoting has not been up there, the quotation is about a different house.
About Spanish and Mediterranean houses
Ask where the line set will run on the outside, and ask for it to be drawn or photographed before work starts. It is the part people live with and the part nobody discusses.
About post-war houses with gravity systems
Ask for the existing duct route to be surveyed and measured, separately from any quotation. Reusing the route while replacing the ducts is often the best value available in this kind of house.
About flats in older buildings
Ask for the published sound level of anything proposed, in decibels, and where that figure is measured from. In a light well it is the number your neighbours will quote back at you.
About already-remodelled houses
Ask for a load calculation against the house as it stands today. The one used last time, if there was one, was for a smaller building.
When it is entirely yours
Then the constraints are the building and the city rather than a committee, and you can make the decision in one afternoon. Two things still worth doing: check whether your property sits in a district with design rules, which is not obvious from the street; and talk to the neighbour whose wall faces your proposed unit before it is installed rather than after. Neither is required. Both are cheaper than the alternative.
When an association decides
Read the note above before anything else on this page. In short: get the approval in writing before ordering, because equipment installed on common property without it can be ordered removed at your cost — and we will not fit it without that approval, whoever is paying.
When you rent
Anything fixed to the building is the owner’s decision and we will not fit it without their written agreement, whoever is paying. What is genuinely yours is a portable or a window unit, which leaves when you do — and if you use a portable, get the exhaust properly outside and block the gap, or it will pull warm air in from the rest of the building and disappoint you. What your tenancy entitles you to is a question for a tenant advice service rather than for us, and we will say so rather than guess.
When there is a shared wall but no association
Then nobody has to approve anything, which makes the neighbour conversation more important rather than less. Two practical points: an outdoor unit in a narrow gap between two buildings is louder next door than in your own house, and a line set or bracket fixed to a party wall is a dispute waiting to happen even where it is technically permitted. We will propose the quieter side of the building even when it costs more in pipe, and we will tell you why.
Four things to settle before anybody orders equipment
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Where the outdoor unit may stand
In writing where anybody else has a say. This single answer decides more of the price than the equipment choice does.
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What the route is, and who makes good
Where the line set or duct runs, inside and out, and who repairs the plaster, the stucco and the paint afterwards. Agree it before, not after.
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The load, calculated against the house as it is now
Not the house as built, and not the tonnage already installed. Older houses have usually changed more than their systems have.
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The sound figure, and where it will be heard
Published, in decibels, and considered from the neighbour’s window as well as your own. It is the complaint that arrives six months later.