Questions to Ask When Buying an Old House
For buyers considering an older home: what to ask the seller, the agent, and your inspector about wiring, pipes, heating, asbestos and lead, foundations, water intrusion, permits, and the restrictions that come with a historic district.
The questions
Open any question for the note
When was the house built, and what major work has been done since, by whom, and under permit?
Why ask it
The build date tells you which era's materials and methods you are dealing with, but the work history tells you who has been inside the walls. Ask for permit numbers and contractor names, because unpermitted work is both a negotiating point and something your insurer or a future buyer's lender can object to.
Is the property in a historic district, or subject to design review, a preservation easement, or any local ordinance?
Why ask it
In a regulated district, replacing windows, siding, roofing, or even paint colours can require approval, and approval often means the more expensive option rather than the one you wanted. This is the single item most likely to change what owning the house costs, and it is rarely volunteered.
What kind of wiring does the house have, what is the panel amperage, and are the outlets grounded?
Why ask it
Knob and tube wiring, cloth insulated cable, a fuse box, or a 60 amp service all limit what you can run and can lead an insurer to decline the property or demand an upgrade as a condition of cover. Ask them to open the panel and photograph it, and count the two prong outlets as you walk through.
What are the water supply pipes and drain lines made of, including the line from the street?
Why ask it
Galvanized steel supply lines rust closed from the inside and show up as weak pressure upstairs, cast iron drains crack at the joints, and a lead service line is a specific issue worth confirming with the water utility rather than the seller. Look under sinks and where the main enters the basement, and run two taps at once.
How is the house heated, how old is that system, and has there ever been an oil tank on the property?
Why ask it
A steam or hot water system with an old boiler can last a long time or fail within a year, and the answer depends on service records rather than appearance. A buried or abandoned oil tank is the item to press on, because a leaking tank becomes an environmental cleanup the new owner pays for, and old tanks are sometimes forgotten rather than concealed.
Are there known asbestos containing materials, and where?
Why ask it
Pipe and duct wrap, floor tile and its adhesive, some siding and roof shingles, and textured ceilings are the usual places in an older house. Undisturbed material is generally left alone, so the practical answer you want is where it is, so you know which renovation plans just became abatement projects.
Has lead paint been tested for or disclosed, and where is paint chipping or on a friction surface?
Why ask it
Homes built before 1978 come with a lead paint disclosure in the United States, and the risk sits in windows, door jambs, and stair rails where paint rubs and creates dust rather than in intact walls. If small children will live there, get the actual test results instead of a form saying nothing is known.
What is the foundation made of, and what condition are the sills, joists, and basement or crawl space in?
Why ask it
Rubble stone, brick, and block all behave differently, and the expensive damage in an old house is usually at the sill, where wood meets masonry and moisture collects. Look for jacked posts, new lumber sistered to old, and powdery mortar, then ask what prompted each of those repairs.
How old is the roof, how many layers of covering are on it, and when was the flashing last addressed?
Why ask it
Multiple layers mean the next roof includes a tear off, and on older houses the leaks usually start at chimney and valley flashing rather than in the field of the roof. Ask about stains in the attic rather than only about the shingles, because the attic is where the truth is.
Are the chimneys lined, still in use, and when were they last inspected or swept?
Why ask it
An unlined or deteriorated flue on a working fireplace or an appliance vent is a fire and carbon monoxide risk, and relining is a real expense. A chimney that has been abandoned but not properly capped becomes a water entry point straight into the middle of the house.
Are the windows original, are there storm windows, and would replacements need approval?
Why ask it
Original sashes can often be repaired and weatherstripped for less than replacement, which matters because in a regulated district replacement may not be permitted at all. Ask whether the sash cords work and whether the windows have been painted shut, since that is what determines whether they function.
Has water ever come into the basement or crawl space, and what was done about it?
Why ask it
Almost every old basement has taken water at some point, so the useful answers concern the source and the fix: gutters and grading, a sump, an interior drain, or an exterior excavation. Fresh paint on a foundation wall, a new sump with no discharge, and a dehumidifier running in a dry season are all worth asking about directly.
Where is the house insulated, and has anyone added insulation to the walls?
Why ask it
Old walls were built to dry out, and blown in or foam insulation added without a plan for moisture can trap it inside the assembly, which shows up years later as paint failure or rot. Ask what was installed, by whom, and whether anything was done about air sealing and ventilation at the same time.
What is the pest history: termites, carpenter ants, powder post beetles, or rodents, and is there a treatment warranty?
Why ask it
In an older house the question is not whether insects have visited but what structural damage they left and whether it was repaired. A transferable treatment warranty is worth asking for by name, and old bait stations around the foundation are a sign there is a history to discuss.
Is the house on public sewer or septic, and has the line been camera inspected or the tank recently pumped?
Why ask it
A sewer lateral on an old property can be clay, root filled, or collapsed, and replacing one under a street or a mature garden is expensive enough to change your offer. On septic, ask for the last inspection and pumping records and whether the system is sized and permitted for the number of bedrooms you plan to use.
Have radon and, if applicable, well water tests been done, and can I see the results?
Why ask it
Both are cheap to test and neither is visible, and radon in particular varies house by house rather than by neighbourhood, so a neighbour's result proves nothing. Ask for dated results and whether any mitigation system on site is still working.
Who insures the house now, what does it cost, and have you had any claims or been refused cover?
Why ask it
Old wiring, an aged roof, an oil tank, or a claims history can make a house expensive or impossible to insure, and you would rather learn that during diligence than after your offer is accepted. Ask for the current premium and get your own quote on the specific address before you commit.
Were the additions, finished attic, or finished basement permitted, and do they meet current requirements for egress and ceiling height?
Why ask it
A bedroom without a proper exit window or a stairway that no longer meets code can affect insurance, resale, and appraisal, quite apart from safety. Ask to see the permit and the final inspection sign off, since a permit pulled but never closed out is a common and awkward finding.
Can I bring in specialists before I commit: a structural engineer, a sewer camera, a chimney sweep, and asbestos or lead screening?
Why ask it
A general inspector will flag areas of concern but will not open a chimney, run a camera down a drain, or price a structural repair. Refusal, or a deadline too short for these to happen, is itself information about what the seller expects them to find.
What would you deal with next if you were staying, and what does the house need in the next five years?
Why ask it
Framed this way the seller answers as an owner rather than as a defendant, and the list you get is usually more honest and more specific than any answer to a question about problems. Someone who has lived with an old house knows exactly which item is due next.
Evaluating an Older Home
Practical guidance for the conversation itself
Assemble the Right Help
Hire an inspector who works on houses of this age
Ask candidates how many houses from this period they inspect a year, whether they will enter the crawl space and the attic, and how they handle knob and tube wiring, rubble foundations, and steam heat. An inspector who mainly covers recent construction will describe an old house as a list of defects rather than telling you which items are normal and which are urgent.
Add specialists where the money is
A sewer camera, a chimney inspection, and where relevant a structural engineer or an asbestos survey each cost a fraction of the repair they might uncover. Book them during the inspection period rather than after, and ask the seller's agent for access at the time you make the offer so the schedule works.
Get insurance quoted on the address, not on a guess
Call an agent with the year built, the wiring type, the roof age, the heating system, and any oil tank history. A declined or heavily loaded quote is a genuine reason to renegotiate or withdraw, and it is much better to hear it while you still have an inspection contingency.
Visit the local building department
Permit records show what was done legally, what was opened and never closed out, and sometimes old plans. In a historic district, the same visit tells you what you would be allowed to change, which is more reliable than an agent's recollection.
What to Look at Yourself
Go to the basement and the attic first
Those two spaces are where the house is undisguised. In the basement look at the sill, the joist ends, the base of posts, water staining, and pipe material. In the attic look for daylight, stains around the chimney and valleys, insulation depth, and whether bathroom fans vent outside or just into the roof space.
Read the repairs, not just the finishes
New lumber beside old, a jack post under a beam, fresh mortar in one section of wall, or one repainted foundation wall each mark a problem someone dealt with. None is automatically bad. Each is a question about what caused it and whether the cause was fixed or just covered.
Test what is easy to test
Run two taps at once and flush a toilet to judge pressure, fill a tub, open and close every window, and try light switches in every room. Walk the floors and note where they slope; an old house with a consistent settle is different from one with a new dip in a single spot.
Walk the outside at ground level
Check that soil slopes away from the foundation, that downspouts discharge away from the wall rather than into the ground next to it, and that no bed of soil or mulch sits against wooden siding. Most basement water problems in old houses are surface water problems first.
Where Buyers Get Caught
Budgeting for the renovation you want, not the systems you inherit
Kitchens photograph well; wiring, plumbing, heating, roofing, and drainage do not. Get quotes on those before allocating anything to cosmetics, because they usually consume the first years of your budget.
Assuming you can change what you see
In a regulated district, windows, siding, porches, and roofing may be controlled, and permission can take months. Confirm what is allowed before you buy on the strength of a renovation plan.
Treating old materials as automatic emergencies
Undisturbed asbestos, intact lead paint, and working knob and tube wiring are managed situations rather than instant crises, and panic pricing serves nobody. Get advice on what needs removal, what needs monitoring, and what only matters when you renovate.
Letting the inspection period run out
Specialist visits need scheduling, and sellers are often slow to grant access. Ask for a period long enough to fit them in, and start booking the day your offer is accepted rather than waiting for the general inspection report.
Forgetting the oil tank
An abandoned underground tank can sit unrecorded for decades and become the owner's problem when it leaks. Ask directly, look for filler pipes and vent lines against the exterior wall, and consider a tank sweep where oil heat was once common.
Documents and Records to Ask For
- Permit history and final inspection sign offs for all past work
- Seller's disclosure statement, plus the lead paint disclosure for homes built before 1978
- Any asbestos survey, radon test, or well water test results
- Oil tank records: installation, removal, decommissioning, or a tank sweep report
- Sewer camera report, or septic inspection and pumping records
- Chimney inspection reports and relining documentation
- Roof invoices, showing tear off or layer count and flashing work
- Pest inspection reports and any transferable treatment warranty
- Current insurance policy, premium, and claims history for the address
- Utility bills across a full year, especially a winter month
- Historic district guidelines and any approvals or conditions attached to the property