Quality & specification

The small print, done properly

Choosing a worktop should be about colour, feel and how it suits your kitchen. The technical side matters too, so we’ve done that homework for you. Here’s what we checked, and what it means for you, in plain English.

New to quartz? Start with What is a quartz worktop?

What we checked

• Low silica. Tested by SGS, an independent laboratory. Kinder to the people who cut and fit your worktop.
• Food safe. Certified for direct contact with food, so you can knead, roll and prepare straight on the surface.
• Fresh indoor air. GREENGUARD Gold certified for very low chemical emissions.
• 15-year warranty on the material, with one point of contact from survey to fitting.

Low silica: why we care

You may have heard about silica in the news. Here’s the short version.

Crystalline silica is one of the most common minerals on Earth. It’s in sand, soil, rock, brick and concrete, so it’s all around us every day. Quartz worktops are made mostly from crushed stone, so they contain it too. Once your worktop is fitted it is completely safe. There’s no dust, nothing is given off, and there’s nothing to worry about.

The risk is to the people who cut and polish the stone before it reaches you. Breathing fine stone dust over many years can seriously harm their lungs. In May 2026 the Health and Safety Executive asked the industry to choose the lowest-silica stone available, and set out minimum standards for cutting and polishing it safely.

That’s why we chose low silica for Redwood Select. Traditional quartz can be up to 90% crystalline silica. Every rated colour in our range has been tested by SGS, an independent laboratory, and comes in well below that. Our fabrication partners cut and polish to the HSE’s standards, with wet cutting and proper protection.

What the ratings on each colour mean

• Low silica: under 40% crystalline silica in independent SGS testing. Traditional quartz can contain up to 90%.
• Ultra-low silica: under 10% crystalline silica in independent SGS testing.
• Silica not detected: the laboratory found no crystalline silica.

We order factory-labelled low-silica slabs for every Redwood Select kitchen. If a colour doesn’t show a rating yet, it’s simply waiting for its test results. Just ask and we’ll tell you what we know.

Tracked from the factory to your kitchen

Every slab is labelled at the factory with its batch and shade number, and low-silica slabs are marked LS. Our importer and fabrication partners use these labels when they pick and cut your worktops, keeping the colour consistent across your kitchen.

Bookmatched slabs are labelled A and B, so each pair is cut and fitted as a mirror image.

Food safe, and easy on the air you breathe

NSF food zone

NSF is an independent public-health organisation. Its food-zone certification means the surface is suitable for direct contact with food and easy to keep clean and hygienic. It’s made for real family cooking.

GREENGUARD Gold

Many things in our homes release small amounts of chemicals into the air, especially when they’re new. GREENGUARD Gold, run by the safety organisation UL, confirms a product’s emissions are very low. Gold is the stricter level, the one used for schools and healthcare buildings, which makes it a natural fit for a family kitchen.

These are the manufacturer’s certifications, as shown on the product labelling.

The practical details

• Thickness: 20mm for a slim, modern edge, or 30mm for a more substantial look.
• Slab size: most colours come in slabs of 3200 × 1600mm, and some in 3300 × 1650mm. Before cutting, the outer edge of every slab is trimmed away. It’s standard practice and helps prevent cracking, so allow for a usable area around 6cm smaller each way: roughly 3140 × 1540mm from a 3200 × 1600mm slab.
• Joints: if your worktop needs a joint, we’ll plan where it goes with you and keep it as discreet as possible. More about joints.
• Finish: polished for a glossy shine that bounces light around the room, or silk for a soft, velvety sheen.
• Bookmatched: two slabs whose patterns mirror each other, like an open book. Lovely on islands and splashbacks. As with natural stone, the match is close rather than perfect.
• Translucent: a few colours can be lit from behind for a glowing feature. This only works with the 20mm version of the slab.
• Printed: a manufacturing technique used on some colours, where the veining is built up in layers as the slab is made, for crisp, natural-looking detail.

Looked after for 15 years

Every Redwood Select worktop has a 15-year warranty against manufacturing defects in the material, from the day it is fitted. And because we manage everything from survey to fitting, you will always know who to call. Read the full warranty terms (opens in a new tab).

Questions? We’re happy to talk it through

Bring them along to your free survey, or call us on 0118 321 8286.