Refractory Powdered Fire Clay | 25kg Bag
Heat-resistant refractory mortar and render. Mix with water for pizza oven domes, walls and floors, fire brick bedding, jointing and repairs.
£35.49
Regular price
In stock
£35.49
Need help choosing?What is refractory powdered fire clay?
This is a 25kg bag of powdered fire clay for high-temperature masonry. Mixed with clean water, it is used as a heat-resistant refractory mortar or render — not only as a dry jointing powder.
It is suitable for bedding and joining fire bricks, pointing joints, gap filling, patch repairs, and pizza oven dome, wall and floor work where the chosen construction method specifies fire clay mortar.
What can refractory fire clay be used for?
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Pizza oven dome construction
Use as refractory mortar or render when building or repairing a pizza oven dome that calls for fire clay rather than a different jointing compound.
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Pizza oven walls and floors
Suitable for oven walls and for floors where the construction method specifies bedding or rendering with fire clay mortar.
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Bedding and jointing fire bricks
Mix to a workable mortar for laying fire bricks, pointing joints and filling gaps in heat-facing masonry.
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Refractory repairs and rendering
Useful for patch repairs and heat-resistant render on suitable fireplace, stove and BBQ masonry, applied in controlled layers.
How to mix and apply
Treat mixed fire clay as a refractory mortar or render. Work it onto clean, suitable masonry or firebrick surfaces. Exact water ratios, coat thicknesses and drying times vary by project, so follow your chosen construction method.
- Mix gradually Add clean water a little at a time until you have a workable mortar or render consistency.
- Avoid an overly wet mix A sloppy mix is harder to control and slower to dry.
- Prepare the surface Apply to clean, suitable masonry or firebrick surfaces.
- Bed, joint or repair Use for bedding bricks, filling joints, patch repairs, and suitable dome, wall or floor refractory work.
- Render in layers For rendering, apply in controlled layers rather than one excessively thick coat.
- Dry before heating Allow the completed work to dry thoroughly before introducing significant heat.
- Cure with small fires Increase heat over several firings rather than taking the oven or fireplace straight to full temperature.
Pizza oven mortar and fire brick work
Pair this bag with Premium Clay Fire Bricks where 230 × 114 × 25mm bricks are specified. Shop related materials in BBQ DIY Pizza Oven Parts and see an example build in our wood-fired pizza oven guide.
The same fire clay mortar is used in masonry BBQ examples such as the Turkish-style charcoal BBQ and Argentinian-style BBQ grill guides, where fire bricks need bedding and pointing.
Drying and curing refractory fire clay
Allow the completed work to dry thoroughly, then begin with small, gentle fires and progressively increase the fire size and temperature over subsequent firings.
Do not immediately take newly completed work to full operating temperature. Rapidly heating material that still contains moisture can contribute to cracking or steam damage. This is practical general guidance, not a promise that cracking will not occur.
Specifications
- Product
- Refractory powdered fire clay
- Bag size
- 25kg
- Form
- Dry powder, mixed with water to a mortar or render
- Fusion point
- Above 1600°C
- Typical uses
- Pizza oven domes, walls and floors; fire brick bedding and jointing; pointing; gap filling; refractory repairs; suitable fireplace, stove and BBQ masonry
What else do I need?
Premium Clay Fire Bricks
230 × 114 × 25mm clay fire bricks for stoves, fireplaces, pizza ovens and BBQs.
DIY pizza oven parts
Fire bricks, refractory clay and related materials for oven and BBQ builds.
Wood-fired pizza oven guide
Example pizza oven with fire brick quantities and where this clay is used.
Turkish-style charcoal BBQ
Example masonry BBQ using fire bricks and refractory clay.
Handling & Safety
This is a powdered fireclay and dust should be kept to a minimum during handling and mixing. Avoid breathing airborne dust. Mix in a well-ventilated area and wear suitable respiratory protection where adequate ventilation is not available. Eye protection is recommended.
Avoid dry sweeping spilled material. Use a suitable vacuum system or lightly dampen the material to help control dust during clean-up.
Refractory construction methods vary by project. Follow the requirements of your chosen oven, fireplace or masonry design and use suitable materials and construction methods. The Stove Wizard cannot accept responsibility for failures caused by incorrect mixing, application, construction, drying or curing.
Frequently asked questions
What is refractory fire clay used for?
Mixed with water, it is used as heat-resistant mortar or render for bedding and jointing fire bricks, pointing, gap filling, patch repairs, and pizza oven dome, wall or floor work where fire clay is specified.
Can refractory fire clay be used as mortar?
Yes. Add clean water to a workable mortar consistency for laying fire bricks and filling joints. It is not a ready-mixed fire cement.
Can I use fire clay for a pizza oven?
Yes, where the oven design specifies fire clay mortar or render. Follow that construction method rather than treating this bag as a complete oven kit.
Can it be used for a pizza oven dome?
Yes, for building or repairing a dome when the chosen method calls for fire clay rather than another refractory jointing material.
Can it be used for pizza oven walls and floors?
Yes, for walls and for floors where the construction method specifies bedding or rendering with fire clay mortar.
Can it be used for bedding and jointing fire bricks?
Yes. That is a primary use: mix to a workable mortar, bed the bricks and point the joints on suitable heat-facing masonry.
How do you mix powdered fire clay?
Add clean water gradually until you have a workable mortar or render consistency. Do not make the mix excessively wet. Exact ratios are not listed, so mix to the feel required by your method.
Does refractory fire clay need curing?
Allow the work to dry thoroughly, then start with small gentle fires and increase heat over later firings. Rapidly heating damp material can contribute to cracking or steam damage.
What is the difference between refractory fire clay and ordinary mortar?
This is powdered fire clay mixed with water for high-temperature masonry. Ordinary sand-and-cement mortar is not a substitute where a fire clay or refractory mortar is specified.