Shay Lally Quantity surveyor

IN OUR NEW series, The Big Reno Clinic, Houses to Restore QS Shay Lally provides answers and solutions to the big (and little, but important) questions you may have about making the most of your home.

Send your question to reno@thejournal.ie. 

This week’s question:

I’m looking at buying a 1930s cottage that has no central heating. Without any extension etc, how much would it cost to bring it up to scratch? The BER is G and the roof is just a wood panel, covered with roof tiles.

Shay says:

Let’s start with the bit nobody wants to hear: without seeing the house, I can’t give you an exact figure – anyone who tells you otherwise is guessing. What I can do is tell you the reality of what you’re buying, and the scale of the job ahead.

Here’s the honest version: you’re not really buying a cottage. You’re buying a shell.

Here’s why. To fix that BER G rating, the house needs to be stripped back to the bare walls. To replace a wood-panel roof, the existing roof comes off entirely. And if you plan to extend, you’ll be knocking through walls to connect the old house to the new build. When you add all of that up there’ll be very little of the “original cottage” left standing by the time the builders are done.

The good news is that a blank canvas is often easier to work with than a house full of half-decent bits you feel obliged to keep. The catch is that it’ll obviously cost you a lot of money!

What it actually costs

Since I don’t know the cottage’s footprint or your extension plans, here are high-level rates to help you build your own ballpark budget. Please consider these as budgetary guide costs only.

The real numbers tighten up once the house is assessed, the plans are drawn up, the scope of works is established, and the finishes are decided upon:

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You’ll notice a wide variance in the costs I’ve provided above. This is because when you’re at the early stages of a project like yours, and the finer detail, site location and access aren’t known, a quantity surveyor can only provide you with costs for budgetary purposes.

As more information is known about the project and decisions are made, costs become more accurate.

Two worked examples

Example 1 — 80m² cottage + 30m² extension, generous access, nicer kitchen

• Strip out: €15,000

• New roof: €28,000

• Refurb (80m² @ €2,500/m²): €200,000

• Extension (30m² @ €4,500/m²): €135,000

• Knock-through: €8,000

• Kitchen (cabinetry, Dekton worktops, appliances): €32,000

Total (incl. VAT, excl. professional fees): €418,000

This assumes a deep retrofit improving the BER from G to A2, new roof, full kitchen, an en-suite and bathroom fit-out, a 30m² extension, and generous side access for the build. It also assumes you like a nice kitchen.

Example 2 — 60m² cottage + 20m² extension, terraced, tighter budget kitchen

• Strip out: €12,500

• New roof: €28,000

• Refurb (60m² @ €3,000/m²): €180,000

• Extension (20m² @ €5,000/m²): €100,000

• Knock-through: €6,000

• Kitchen (cabinetry, quartz worktops, appliances): €24,000

Total (incl. VAT, excl. professional fees): €350,500

Same scope of works, but this cottage needs more remedial work and has no side access — hence the higher per m² rate – and the kitchen spec is more modest.

Why the two examples land so differently: it’s rarely one factor. Access for machinery and materials, the underlying condition of the walls and foundations, and how much you want to spend on kitchens and finishes have a massive impact on the total cost of renovating and extending

Don’t forget the grants

Before you panic at those totals, check out what grants are available to you
the Vacant Property Refurbishment Grant (funded through the Croí Cónaithe Towns Fund) is the big one.

Related Reads

Rip the plaster off in one go: why renovating bit by bit could cost you double

What does it cost to rewire a 1930s two-up, two-down?

What would it cost to re-do an old, small, extension?

If the property has been vacant for two years and meets the criteria, you can get up to €50,000. If it’s also confirmed derelict, there’s a top-up bringing the total to €70,000.

Two things to be aware of – you apply before starting work and must finish within 13 months of approval, and the money is paid out after the works are complete — so you’ll need to fund the build first and get reimbursed after

SEAI grants are split across two routes:

• Better Energy Homes — grants for individual upgrades (attic and wall insulation, windows and doors, heating controls, heat pumps, solar), with amounts varying by house type

• National Home Energy Upgrade Scheme — typically delivered through a “one-stop shop” provider, though you can also access the same funding via an SEAI-registered project coordinator working with your own contractor. (SEAI increased several grant amounts in early 2026, so check seai.ie to establish how much you qualify for)

Between the two schemes, there’s a meaningful chunk of funding available that would knock a real dent out of the figures in the examples above.

Final thoughts

A 1930s cottage with no heating and a poor rating in the condition you’ve described is a big undertaking. My advice would be to develop a brief of what you’d like to do with the cottage and get some budgetary advice from a quantity surveyor who has experience with similar projects.

It’s also worth calculating how much you’ll likely spend in total between buying the property, renovating and extending it, along with the professional fees involved with the work and the transaction.

From there I’d establish how much the property would sell for if you went to sell it after all of the work was done. If you don’t believe you’d get your money back on the property, it might be worth reconsidering your plans and opting for a property that makes better financial sense.

That said, please disregard this point if you consider this property to be your forever home. 

Key takeaways

• You’re buying a shell, not a cottage. Fixing the roof, the BER, and any extension plans means stripping the house back to its bare walls.

• Budget €350,000–€420,000+ for a full retrofit-plus-extension on a cottage this size, including VAT but excluding professional fees — and that’s before you’ve seen the actual site.

• Costs swing on three things: site access, the condition of the existing structure, and how much you want to spend on finishes.

• Grants can claw back real money — up to €70,000 from the Vacant Property Refurbishment Grant plus SEAI energy upgrade funding — but it’s paid retrospectively, so you need to fund the build up front.

• Get a QS involved early. Budgetary costs become more accurate after the brief is considered and decisions are made.