Older houses cost more per square foot to remodel, consistently and predictably, and the reasons are specific rather than mysterious. This guide puts numbers against each of them so a budget can be built that survives contact with the demolition.
For the process and sequence of an old house project, see our guide to old house renovation. This one is about the money.
The line items newer houses do not have
Electrical. A pre-war house frequently has a 60 or 100 amp service and may have knob and tube remnants. A full rewire runs $12,000 to $30,000 depending on size and access; a service upgrade alone is $2,500 to $5,000. Insurers increasingly ask about knob and tube, which sometimes forces the timing.
Plumbing. Galvanised supply lines corrode from the inside and restrict flow long before they leak. Replacing supply throughout runs $8,000 to $20,000. A cast iron waste stack at the end of its life adds $3,000 to $9,000.
Insulation and air sealing. Most pre-war walls have nothing in them. Dense-pack cellulose into existing wall cavities runs $3 to $6 per square foot of wall; doing it properly while walls are open costs less and performs better.
Plaster. Repairing and keying original plaster is skilled work and costs more than hanging drywall. Replacing it with drywall is cheaper and changes how the rooms read, which is a real trade-off rather than an obvious saving.
Non-standard everything. Door openings, window sizes, stair dimensions and floor levels in an old house are not standard, so stock components frequently do not fit and things get made instead of ordered. This is a labour premium that runs through the whole project.
What moves the price
- Whether walls are opening anyway. Systems work is dramatically cheaper when it can be done through open walls rather than fished through finished ones.
- Access. Row houses and houses on tight urban lots cost more in labour because everything is carried in and out through a narrow hall.
- Previous bad work. Nearly every old house has at least one earlier renovation that has to be undone before the new one can start.
- Historic district requirements. Where they apply, exterior changes may need review and specified materials.
Mistakes we see most often
- Using a per square foot figure from a newer house to budget an older one.
- Holding a ten percent contingency on a pre-war house. Fifteen to twenty is realistic.
- Doing systems work piecemeal, room by room, rather than once while walls are open.
- Budgeting for the rooms and forgetting the envelope, which in this climate is where the running costs live.
What this means in the Capital Region
For an older Capital Region home, a realistic budget includes an explicit line for electrical service and rewiring, one for supply plumbing, and one for insulation, before any kitchen or bathroom is priced. In a house from the 1890s or 1900s in Troy, Albany, Cohoes or the Schenectady Stockade, the probability that all three are needed is high.
Those three together frequently run $25,000 to $50,000 on a mid-sized house, and they produce no visible change whatsoever. Knowing that at the start is the difference between a budget that holds and a project that runs out of money before the finishes.
Want this priced for your own home? Jeffrey Mason will walk the project and give you a free written estimate. No obligation, no sales rep. Call (518) 308-6427.
Frequently asked questions
Why do old houses cost more to remodel?
Systems that need full replacement, no insulation, plaster rather than drywall, non-standard dimensions that force custom work, and almost always some previous bad renovation that has to be undone first.
How much should I budget for wiring and plumbing?
A full rewire runs $12,000 to $30,000 and supply plumbing replacement $8,000 to $20,000 on a mid-sized house. Both are dramatically cheaper if done while walls are already open for other work.
Should I keep the plaster?
It costs more to repair than to replace with drywall, and it holds sound better and reads correctly in a period room. It is a genuine trade-off rather than an obvious saving either way.
What contingency do I need?
Fifteen to twenty percent on a pre-war house, against ten on a newer one. On an old house the contingency is not padding, it is a realistic estimate of what cannot be seen yet.
Related guides
- Old House Renovation: Updating Without Losing Character
- Custom Home Remodeling: Tailored Solutions for Every Room
- High-End Remodeling: What to Expect From a Premium Contractor
- Interior Home Remodeling: Room-by-Room Transformation Guide
- Interior Remodeling Contractors: What They Do and How to Find One
- Interior Remodeling Guide: Room-by-Room Planning