What a Shellcrete pool deck costs, and what moves the number

Most contractors will not put a number on a page. That is understandable, and it is still unhelpful — you cannot plan a project around "call for pricing", and the reason people ask is that they are trying to work out whether this is a five thousand dollar job or a thirty thousand dollar one.

So this page does two things. It tells you what we start at. Then it spends most of its length on what actually decides your number, which is not the surface you choose — it is the slab underneath it.

We have poured Shellcrete on more than four hundred projects. Everything below is what that taught us about why two decks of the same size are not the same job.

What we start at

Shellcrete is priced from $20 per square foot installed. That is a starting point, not a quote, and every job is priced after somebody has stood on the slab.

It is the expensive end of the pool-deck market and it should be. It is a placed, hand-finished surface with real shell aggregate in it, and the finishing is skilled labour that cannot be hurried.

What pushes a quote up

The condition of what is already there. This is the single biggest variable. A sound, flat slab is the cheap case. A slab with active cracking, spalling, or previous coatings that have to come off is not. Slabs that are moving because the ground under them is moving have to be addressed structurally before any surface goes on, and no topping fixes that.

Access. A deck you can reach with a wheelbarrow costs less than a deck reached through a house or over a screened enclosure. Barrier-island jobs frequently mean a longer carry and tighter parking.

Edges, steps and coping. Flat area is the cheap part. Every step nosing, radius, drain and coping run is hand work. A rectangular deck and a freeform deck of the same square footage are not the same job.

Finish. More grinding is more time.

Removing something first. Old pavers, old tile and failed coatings all have to come off and go somewhere, and disposal in this county is not free.

Why the square-footage question does not have an answer

People ask "what is your price per square foot", and it is a completely reasonable question. The reason it cannot be answered honestly over the phone is that on a resurfacing job the surface is often less than half the cost. The prep is the job.

A 700-square-foot deck in good condition and a 700-square-foot deck with a failed coating and three settled sections are different projects that happen to share a number.

Anybody who gives you a firm price without seeing the slab is either padding for the worst case or is going to find something once the work starts.

What to ask any contractor

Ask these of us and of whoever else you are talking to.

• What exactly are you doing to the existing surface before the new one goes on?
• Where are the control joints going, and why there?
• What is the sealer, and when does it need doing again?
• What is warranted, for how long, and what voids it?
• Is there a written allowance for what you find under a failed coating?

A contractor who answers those five clearly is more likely to be right about the price than one who is simply cheaper.

Two things worth reading before that call: whether a cracked deck should be repaired or resurfaced — some should not be resurfaced at all — and the three finishes, because the finish is decided before the pour, not after it.