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Gas Pipe Sizing (BS 6891) Calculator
Minimum copper gas pipe size from appliance input and effective pipe length, to BS 6891 (1 mbar drop). Gas Safe work only — always verify on site.
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Browse the full shop →Frequently asked questions
How do I use the gas pipe sizing (bs 6891) calculator?
Enter your measurements and options into the Gas Pipe Sizing (BS 6891) above and the result updates instantly. Minimum copper gas pipe size from appliance input and effective pipe length, to BS 6891 (1 mbar drop). Gas Safe work only — always verify on site.
Is the gas pipe sizing (bs 6891) calculator free to use?
Yes — every TradesMate calculator is free to use with no sign-up. Save quotes and use the full estimator with a free trial.
Are the results accurate enough to quote from?
The figures are reliable estimates based on standard UK trade practice. Always allow for wastage and verify against current material prices before quoting a customer.
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