Before you write the offer
What inspections turn up in a Denver house, by era
Every era of Denver house has its own short list of expensive problems. Knowing it before you write gives us room to negotiate; the inspector tells us what is actually there.
I’ve sat through a lot of Denver inspections. This is what usually comes up. I’ll be at yours, and I’ll help you read what actually did.
By Ryan Garvey, Broker Associate, Compass · Updated
Before 1940
The old stock
Victorians, Denver Squares, bungalows and the first Tudors. These are the best-built houses in the city and the ones that will empty your account fastest if you buy the wrong one. Almost everything expensive here is buried, behind plaster, or under the floor.
The sewer line
A general inspection stops at the foundation wall, so this needs its own sewer scope, ideally before we go under contract. On a house this age the line out to the main is usually clay tile laid in four-foot sections, and the camera is looking for root intrusion at the joints, bellies where water sits, and any section that has shifted.
A full replacement out to the street runs five figures, more if the line crosses an alley or a mature tree has to come out. Find it before the offer and it is a price conversation; find it after closing and it is your money.
Knob-and-tube and ungrounded outlets
The inspector pulls the panel cover and looks in the attic and basement for the old ceramic knobs and the cloth-sheathed runs, then tests whether the three-prong outlets someone swapped in actually have a ground behind them. On houses this age I have watched that test fail more often than it passes.
Several insurers will not write a policy on active knob-and-tube, and that can surface late enough to threaten your closing. A whole-house rewire is a serious number, and the half-measure where a previous owner grounded the outlets but not the circuits is worse than the original problem.
The brick and the mortar
Original lime mortar is soft and sandy on purpose, and you can often see from the sidewalk whether somebody has repointed with hard grey portland mortar or a wall is stair-stepping above a window. If the inspector flags either one, the next call is to a structural engineer, not to anyone's opinion, mine included.
Denver's unreinforced brick is beautiful and it is also the thing that moves. Repointing a wall properly is a real bill, and hard mortar on soft brick keeps spalling the face of the brick for as long as it is in there.
Soil movement and the foundation
Our clay swells when it gets wet and shrinks when it dries, and the house rides on top of that. The inspector looks at the basement walls for horizontal cracks and at the floors for slope. On a showing, watch the doors: a house that has moved tells you at the door jambs before it tells you anywhere else.
Most of these houses have moved a little and that is fine. The ones that are still moving need piers or a drainage fix, and the difference between those two outcomes is the difference between a few thousand dollars and a very bad year.
The old furnace and its ductwork
If the house still has an octopus gravity furnace, or a forced-air unit stuffed into the bones of one, the inspector looks at how the conversion was done and at what the duct wrap is made of. Ask whether the chimney was lined when the appliance changed; I have seen that question catch more than one seller without an answer.
An unlined chimney serving a modern high-efficiency appliance is a combustion-safety problem, not a comfort problem. Redoing the conversion properly means new ducting and a liner, and it is far cheaper to negotiate than to discover in February.
Lead paint
Anything built before 1978 comes with a federal lead-based paint disclosure and a ten-day window to test. On a pre-1940 house, assume it is under there, and pay attention to the friction surfaces — windows, door edges, porch rails — where paint turns into dust.
It is not a reason to walk away from a house. It is a reason to know before you start sanding, and if you have small children or plan to open up walls, that changes how you budget the renovation and who you hire.
Galvanised supply lines
On a showing, run a tap upstairs while another one is open downstairs and watch what happens to the pressure; the inspector will look at the pipe where it enters the house. Galvanised steel corrodes from the inside, so it looks fine and flows like a straw.
Repiping a house in copper or PEX is a mid-four-figure to five-figure job and it means opening walls and ceilings. If it needs doing, it is far better done before you move your furniture in.
1940 to 1959
Post-war brick
The brick ranches and small Tudors that make up most of Hale, Mayfair and the middle of Park Hill. They were built well and built cheap at the same time, and almost everything mechanical in them has now reached the end of a second life.
Galvanised supply and cast-iron waste
Same pressure test as on the older houses, plus the waste stack, which the inspector looks at from outside and a sewer scope can see from within. Cast iron rusts from the inside out and usually goes at the hub joints or right where it disappears into the slab.
A supply repipe and a waste-line replacement are separate jobs and separate bills, and a cast-iron failure under a slab means cutting concrete. These are the two that most often turn a tidy-looking ranch into a renovation.
Single-pane windows
Count them on the showing and notice whether the storms are still on. Notice, too, whether anyone has already replaced a few, because a half-finished window job tells you what the last owner ran out of money for.
Twenty original windows is a five-figure replacement, and in the meantime it is your gas bill every January. If the house is in a historic district, the approved options narrow and the price goes up, so we confirm the district before we write.
Swamp cooler penetrations
If there is an evaporative cooler on the roof, ask the inspector to look at the flashing around it and at the decking underneath from inside the attic. If one has been removed, you want to know how the hole was patched.
These leak quietly for years and you find out through a stained ceiling. A patched penetration done properly costs almost nothing; a decade of slow water into the framing is a roof and a ceiling and sometimes a mould remediation.
Aluminium branch wiring in the late-fifties builds
It shows up more in the sixties and seventies, but it starts appearing at the tail end of this era, so ask the inspector to look at the conductors at the panel and at a couple of outlets. What they are looking for is the dull grey of aluminium at the terminal screws.
Aluminium expands and contracts against the screw and eventually loosens, which is how it starts fires. The fix is pigtailing every connection with the approved connectors, which is a day or two of an electrician's time and worth every dollar.
Asbestos in duct wrap and floor tile
The white wrap on the old ducts in the basement and nine-inch floor tile under the carpet are the usual suspects, and both are easy to spot on a showing. Nobody should guess at it, me included: if it looks like a candidate and you plan to disturb it, a lab tests a sample.
Intact and left alone, it is generally not a hazard. The cost lands the day you decide to open up the basement, because abatement has to be done by a licensed contractor and it has to happen before the fun part of the remodel.
A 60-amp service
The inspector reads the main breaker and counts the circuits. A lot of these houses are still on 60 or 100 amps with a panel that has been full since 1994, which is why you see a tangle of extension cords in the basement.
You cannot add a heat pump, an EV charger, or a proper kitchen to a 60-amp service. A service upgrade is a permit, an electrician, and a visit from Xcel, and it is the first thing you will want to do, so price it into the offer.
1960 to 1999
The middle years
Split-levels, tri-levels, and the first wave of suburban-style building inside the city. These houses feel newer than they are, which is exactly the trap: nothing about them looks old enough to worry about, and several of the materials used in them have been recalled.
Polybutylene supply lines
Grey plastic pipe, usually with copper or plastic crimp fittings, common in houses plumbed from the late seventies into the mid-nineties. It is easiest to spot at the water heater and at the shutoffs under the sinks, and you can look for it yourself on a showing.
It fails at the fittings, without warning, and insurers know it: some will not write the house, others will exclude water damage. A repipe is the only real fix, and it is a lot cheaper than one burst line above a finished basement.
Federal Pacific and Zinsco panels
The inspector reads the label on the panel first. Federal Pacific Stab-Lok and Zinsco are the two names I least want to see on a report.
Both have a documented history of breakers that do not trip under load, which means the panel is not doing the one job it exists to do. Replacement is low four figures, and when it shows up on the report it is one of the easiest repairs to ask the seller for.
The roof, and the claim history behind it
The inspector notes the age and type of the shingle, and I ask the listing agent when it was last replaced and whether it went through insurance. Three-tab asphalt on the Front Range takes a beating, and hail here is not hypothetical.
A roof at the end of its life is a five-figure item and can hold up your own insurance binder. It also matters who claimed what and when, because a property with multiple recent claims can be harder and dearer to insure than the house next door.
Aluminium branch wiring
Peak years are roughly the mid-sixties to the late seventies. Ask the inspector to look at the conductors at the panel and pull a couple of outlet and switch plates rather than take anyone's word for it.
Same failure mode as the late-fifties houses and the same fix: pigtail every device with approved connectors. Some insurers ask about it directly, so it is better to have the remediation receipt than to be discovering it at binder time.
Radon
Get a radon test on every house, whatever the zone map says, because radon varies house to house on the same block depending on the soil and how the basement was built.
A mitigation system is usually in the low four figures and takes a day, which is a rounding error against the price of the house. Skipping the test to save a couple of hundred dollars on a home you plan to finish the basement of makes no sense to me.
Furnace and water heater past their service life
The date plates on both tell you most of it, and the inspector will note them. A furnace from the nineties has had a long run, and a water heater over about twelve years is living on borrowed time.
Individually neither is catastrophic; together they are several thousand dollars in the first two years, arriving at the worst possible moment. This is the sort of thing I would rather win as a credit at inspection than pay for in December.
2000 and newer
New construction
Central Park, the infill rowhomes, the scrapes-and-rebuilds. Newer does not mean inspection-free — it means the problems are different, and several of them are about paperwork rather than pipe.
The fee stack, and what each fee buys
In Central Park there is the Master Community Association, and on top of it there is often a sub-HOA for your particular block or building. I get both sets of documents and I read what each one actually covers before you are emotionally committed.
Two fees on one house changes your monthly number and therefore what you qualify for. It also changes who pays when the roof or the siding fails, and finding that out after closing is an expensive way to learn to read documents.
Grading and drainage at the foundation
The inspector walks the perimeter and looks at whether the ground falls away from the house, where the downspouts discharge, and whether the window wells have drains. On new builds this is the item I have seen come back on reports more than any other.
Denver's clay soil plus water against a foundation is how a five-year-old house develops a ten-year-old house's crack pattern. Fixing the grade and extending the downspouts is cheap. Fixing what bad grading does is not.
Low-slope and flat roof sections
A lot of modern infill has a flat or nearly flat section, usually over a rooftop deck or a bump-out. Ask the inspector to look at the membrane, the seams, and how the deck drains, and ask the seller who installed it.
These do not last as long as the pitched roof beside them and they fail differently — a seam lets go and you find out through a bedroom ceiling. Budget for it as its own roof on its own clock, not as part of the main one.
Open builder-warranty items
I ask what warranty is left, what is still open, and whether the builder has been back. On a showing, notice the punch-list items nobody ever came to finish, because a house with three of those usually has more.
Some of these warranties transfer and some do not, and the structural coverage often runs years longer than the workmanship coverage. Knowing which clock you are on decides whether a defect is the builder's problem or yours.
The first replacement cycle
On a house built in the early 2000s the original water heater and often the original furnace and AC are still in there. The inspector will note the date plates; ask the seller for the service records.
The first round of mechanical replacement on a twenty-year-old house lands all at once, and it is several thousand dollars. It is not a defect and it will not usually win you a credit, but it belongs in your plan for year one.
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Tell me which house you are looking at and I will tell you what inspections on houses like it usually turn up, and what to ask before you write. No obligation, and no sales pitch on the phone.
Call or text (802) 236-7346.