Buying a 1970s house in the south metro

Solid aluminum branch circuit wiring was used in many houses built roughly between the mid-1960s and mid-1970s, when copper prices spiked. It is not inherently unsafe sitting in a wall. The known problem is at the connections, where aluminum expands, contracts and oxidizes differently from the copper fittings it is usually joined to, and connections can loosen and overheat over time.

It is one of the few things that can affect insurability. Some carriers decline it, some require remediation, and some are indifferent. Ask your insurance agent before your objection deadline rather than after closing, because an uninsurable house is an unfinanceable one.

Where it is present, remediation is a known job with recognized methods, done by a licensed electrician. What you want to know is whether it has been done, to what standard, and whether it was documented.

Certain panel brands from this era have a long-standing reputation for breakers that may fail to trip, and insurers and inspectors treat them accordingly. A home inspector will identify the manufacturer; what to do about it is a question for a licensed electrician and your insurer, in that order.

Separately from brand, a fifty-year-old panel is often simply too small for how a house is used now. Two electric vehicles, a hot tub, a shop and a heat pump are not a 1972 electrical load. If your plans involve any of that, get the service capacity assessed while you can still price it into the offer.

The line running from the house to the main is the homeowner’s responsibility on most properties, and in houses of this age it is frequently clay or cast iron. Clay joints admit tree roots, and the mature trees that make these streets attractive are the same trees that find the pipe.

A standard home inspection does not include this. It requires a sewer scope, which is a camera run down the line by a separate contractor for a modest fee. On a house of this era it is the optional inspection worth paying for first, because a failed lateral is a yard excavation, and it is the kind of repair that arrives without warning.

Order it early enough that the results land before your inspection objection deadline. Scheduling is the usual reason people skip it, and the deadline does not move because a contractor was busy.

Materials containing asbestos were common in construction into the early 1980s: textured ceiling finishes, some floor tiles and the adhesive under them, pipe and duct insulation. Undisturbed and in good condition, these are generally left alone. The risk is in disturbing them.

That matters because of what buyers of older houses tend to do next, which is scrape the popcorn ceiling and pull up the flooring. Testing before a renovation is inexpensive relative to the remediation that follows doing it in the wrong order, and Colorado regulates asbestos abatement work.

If a renovation is part of why you are buying the house, treat testing as part of pricing the renovation rather than as a separate worry.

It belongs on this list because older houses in this area often have basements and crawl spaces, and because a renovation frequently changes how a lower level is used and ventilated.

Radon is common enough along the Front Range that testing is routine here, and mitigation is a well-understood system rather than a major project. It has its own guide on this site.

Worth saying, because a list of concerns reads worse than the houses deserve. Framing, foundations and roof structure from this era are generally sound, lots are larger than anything built since, and the floor plans have had fifty years of people deciding they work.

Windows, insulation and mechanical systems are the ordinary wear items, and by now many have been replaced at least once. What you are looking for is the paperwork on those replacements: permits, dates, who did the work. A house of this age with a documented history is a substantially better purchase than an identical one without.