What is the difference between an expansion joint and a control joint?

Expansion joints separate slabs or sections so they can move with temperature and moisture changes. Control joints are placed to encourage cracking to happen in a planned line, helping manage random cracks in slabs or long runs of masonry.

When should I use backer rod with sealant?

Use backer rod when you need to control sealant depth and create the right joint shape for tooling. Size the rod so it compresses slightly, and avoid forcing an oversized rod that can distort the joint and lead to a messy finish.

Do you offer pickup and delivery for expansion joint materials?

Yes. You can pick up at our Brentwood, East Setauket, or Riverhead yards, and we deliver across Long Island and into NYC. Call ahead with quantities and we can stage the order for faster loading.

Expansion Joints & Control Joints | 9 Brothers Building Supply

Expansion Joints & Control Joints

If you’re pouring slabs, setting masonry, laying pavers, or running long CMU walls, Expansion Joints & Control Joints are what keep the work looking clean after the first season of movement. On Long Island and in NYC we see big temperature swings, freeze thaw, and a lot of mix and match substrates, so having the right joint material on the truck matters. We stock options that make it easy to separate pours, control cracking, and finish edges without a fight, whether you’re a contractor running multiple jobs or a homeowner tackling a patio and steps.

Types Of Expansion Joints & Control Joints We Carry

Here’s what our crews and customers ask for most, and what we keep moving through the yards:

Expansion Joint Capping
Expansion Joints
Hohmann & Barnard Rubber Control Joint RS-Standard 2-5/8″ X 48″
Fibre Expansion Joint
1/2″ Backer Rod
DECK-O-FOAM Expansion Joint Filler

Real world tip we give at the counter, match the joint to the width you actually need, then plan for compression. If you’re using backer rod and sealant, don’t force an oversized rod into the joint, it can telegraph and make tooling ugly. Bring the joint width and depth, and we’ll help you size it right.

Brand Options We Stock

We keep proven jobsite brands on hand so you can stay consistent from spec to install:

Sika: Great when you’re pairing joints with compatible sealants and accessories, especially for exterior concrete and masonry details where movement is expected.
W.R. Meadows: A go to for dependable expansion joint materials and fillers that contractors use on flatwork, commercial walks, and site work.

If you’re matching an existing spec, tell us what the engineer called out and what you’re tying into. We can usually point you to the closest match fast.

Where These Joints Get Used Around Long Island And NYC

Contractors use expansion joints between slabs, at sidewalks, around columns, and anywhere concrete meets a fixed structure. Control joints are the move for managing crack locations in slabs and long runs of masonry. Homeowners see them show up at patios, garage slabs, stoops, and pool decks.

Another honest tip, don’t skip prep. Clean the joint faces before you set filler or backer rod. Dust and laitance kill bond. If you’re sealing, keep the joint dry and protect it from wash water during cleanup so the sealant doesn’t fail early.

Pickup And Delivery

You can grab Expansion Joints & Control Joints at our Brentwood yard, and we also serve from East Setauket and Riverhead depending on what’s closest to your job. We can load you fast, and for larger orders we’ll stage it if you call ahead with quantities. Delivery is available across Long Island and into NYC, which helps when you’re trying to keep crews moving and materials off tight sidewalks.

Ready When You Are

Tell us what you’re building, the joint size, and whether it’s interior or exterior, and we’ll help you line up the right expansion and control joint materials. Stop by, or call ahead and we’ll stage your order for pickup or delivery.