HDB Maisonette and Executive Flat Renovation

Executive flats and maisonettes are the largest homes HDB built — commonly around 130 sqm, and in the case of maisonettes, spread over two levels connected by an internal staircase. They are also no longer built, which means almost every one you will renovate is a resale unit with decades of history in it.

What makes these flats different

Three things separate an Executive or maisonette renovation from a standard flat:

• Two levels. A maisonette has to be planned as one house, not two floors. Services, storage and circulation all have to work vertically.
• The staircase. It is the defining feature and the biggest constraint. Anything touching it, or any element that may be structural, needs HDB’s written approval — and structural work additionally needs a Professional Engineer’s endorsement.
• Age. These are older blocks. Expect dated wiring, original plumbing and previous owners’ undocumented alterations to surface once work starts.

The staircase question

Most maisonette owners want to open up or update the staircase. Whether that is possible depends entirely on whether the element is structural. Some staircase walls and balustrades can be changed; the structure itself generally cannot. This has to be established before a concept is drawn — not after — because it determines the entire ground-floor plan.

Scope you should expect

A full Executive or maisonette renovation typically spans: the kitchen and its service yard, two or more bathrooms, three or more bedrooms’ worth of carpentry, flooring across both levels, extensive electrical work, and the staircase and double-height area if the design touches them. It is simply a bigger job than a 4-Room flat — more flooring area, more carpentry runs, more wet works.

Timeline reality

These are existing blocks, so HDB’s completion window is generally 1 month from the permit date — the shorter window — despite the larger scope. That is why sequencing matters more here than anywhere else, and why the scope must be settled before the permit is filed. See our renovation timeline guide.

The rules still apply, at a larger scale

The household shelter cannot be hacked or tiled. Floor finishes stay within HDB’s thickness limits. Bathroom floor replacement requires a new waterproofing membrane and a mandatory water test. Water and sanitary work must be done by a PUB Licensed Plumber, and gas work by licensed gas service workers. Full detail in our HDB renovation rules guide.

Where the budget usually goes

In our experience the cost drivers in these flats are carpentry volume, the number of bathrooms being rebuilt, and how much of the old flat has to come out before anything new goes in. Extensive hacking on an older unit is the single biggest swing factor. We scope this on the first visit rather than estimating blind.

Frequently asked questions

Can I change or remove a maisonette staircase?

It depends on whether the element is structural. Non-structural finishes and balustrades can often be changed; structural alterations need HDB’s written approval and a Professional Engineer’s endorsement. This must be confirmed before design work.

How long does an Executive or maisonette renovation take?

These are existing blocks, so HDB generally allows 1 month from the permit date — the shorter window — even though the scope is larger. Tight sequencing is essential.

Are maisonettes harder to renovate than normal flats?

They involve more: two levels, a staircase, more bathrooms and more carpentry, plus the unknowns that come with an older unit. The rules are the same, but there is simply more of everything.

Do you renovate Executive flats and maisonettes?

Yes. We work across every HDB flat type, from 2-Room Flexi to Executive and maisonettes. See our HDB renovation scope by flat type.

Planning your renovation?

Tell us your property type and whether it is a new or resale unit, and we will tell you what is actually available to you before any design work starts.

FC Interior Design — HDB-Approved Contractor (licence HB-09-2619C), Singapore since 1990.
Call +65 6444 0555 or WhatsApp +65 9888 2723.

More reading: all our HDB renovation guides.

See our resale HDB renovation packages for indicative pricing and scope.