Plain OPC, vibrated
The baseline. Polyurethane is the workhorse here on anything without fine detail or undercut. Silicone where the relief demands it.
Knowledge · Materials guide
Choosing a formliner for the mix you actually pour.
The texture is what the architect sees. The mix is what the formliner has to survive. This guide walks through how each common mix type changes the material we'd reach for.
Start here
The mix decides more than people expect.
Most formliner conversations start with the texture and end with the price. The mix gets mentioned in passing. But the mix is what sits against the liner for hours, what the release agent has to cope with, and what determines how the surface wears pour after pour.
Two formliners with the same texture can have very different working lives on two different mixes. That's why we ask about your mix on the first call, even if it's just a line.
Mix by mix
Five common mixes and what they ask of a formliner.
GGBS or fly-ash blends
Slower early strength means longer dwell time on the liner. Not usually a problem for material choice, but it does affect strike timing and how the release film holds up.
Self-compacting concrete
Flows into every detail, which is great for fidelity and hard on liners with thin walls or sharp arrises. We thicken sections and soften arrises that won't survive.
GRC face-mix
High cement content, fine aggregate, sprayed. Silicone usually earns its keep here because it doesn't pick up spray pattern and releases thin shells without cracking corners.
Heavily pigmented mixes
Some pigments and admixtures shorten polyurethane life. If your mix is unusual, tell us — silicone often lasts longer despite costing more up front.
Release
The release agent is part of the mix conversation.
A formliner and its release agent are a pair. Solvent-based releases that suit steel formwork can attack some elastomers. Water-based chemical releases are usually kinder to both silicone and polyurethane.
We'll ask what you use now. If it's compatible, we'll keep it — changing a yard's release regime has knock-on costs. If it isn't, we'll say which family would suit and why.
The handling note that leaves with every liner includes the release regime we designed it around.
What to tell us
Four lines that let us spec the right grade.
Cement type
OPC, blend, or white cement. White cement mixes often have a higher fines content.
Placement
Vibrated, self-compacting, sprayed or hand-packed.
Admixtures and pigment
Anything beyond a standard plasticiser — especially retarders and heavy pigment loads.
Release agent
Brand or family. It changes the grade more often than people think.
At a glance
The idea in a picture.
Where the formliner sits
Swipe to see the whole diagram
FAQs
Common questions on mix and liner.
Do we need a different liner for a winter mix?
Usually not a different material, but accelerated winter mixes shorten dwell time and can change how the release film behaves. Tell us if your mix changes seasonally.
Can one liner serve two different mixes?
Often, yes, if both are within the material's comfort zone. We'd spec for the harsher of the two.
Will a retarder damage the liner?
Surface retarders for exposed aggregate can interact with some polyurethanes. We'll check compatibility before we pour.
Get in touch
Send us a photograph of the panel or the elevation.
One photograph tells us what surface you're chasing, and one line about the mix tells us what silicone or polyurethane will survive it.
Real people, a real workshop
You deal with the people who make it.
No call centre and no middlemen. When you contact TCI Construction, you speak to the team who design, build and check your mould.
- A real Warwickshire workshopUnit 15, Waterloo Park, Bidford-on-Avon, Alcester B50 4JG.
- Real people on the phoneCall the team on 01789 224228, Monday to Friday.
- The same team on every jobDesign, production and aftercare come from the people you see here.
- Part of TCI GroupFive specialist brands, one engineering team. Visit TCI Group.
Thomas LaneManaging Director
George PrestonDesign & Project Manager
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Jim AndertonProduction Manager
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