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Select from the tools available below designed to assist building services engineers, architects and homeowners. 100% Free versions of all tools available now!

pump sizing pipe sizing

Pump Sizing

Easy to use powerful pump sizing spreadsheet, download the free version now and start sizing. Simple to follow video tutorial.

Pipe Sizing

Automatically calculate flow velocities and pipe resistances, simply select your pipe material, size and flow rate. Free to and easy to use.

Fan Sizing

Easy to use powerful fan sizing spreadsheet, download the free version now and start sizing. Quick way to calculate fan duties.


Automatically calculate cross sectional areas, air velocities and duct resistances. Spiral and rectangular calculators all free to use.


Useful conversion tools for engineers including flow rates, power, weights, volumes, areas & lengths. Bookmark now for quick access!

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Water Efficiency

Download the free Part G water efficiency calculator spreadsheet to easily display your calculations for Building Regulation approval.

Heat Pumps

Use the Building Services Portal heat pump assessment calculator to quickly generate a report, with unit sizing and costs advice.

Energy Cost Calculator

Quickly work out how much your household appliances cost to run with our easy to use calculator. Help manage energy costs today.

Photovoltaic Calculator

Answer 4 simple questions to get a quick high-level assessment of possible solar photovoltaic panel generation systems.

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Bob's Blog

Browse Bob's blog for the latest Building Services Portal posts covering a range of topics. Leave a comment to share your views.

Popular Tools

The Building Services Portal pump sizer is the easy to use powerful spreadsheet for calculating pump duties for an heating, chilled water or domestic water system. Guidance notes are including for pump sizing advice and the method is also described step-by-step in the easy to follow tutorial video.

Display your pump duty sizing calculation with the Building Services Portal pump sizing spreadsheet, upgrade the the premium version to have you company logo displayed for professional presentation.

Use the Building Services Portal Water Efficiency Calculator to display your Building Regulations Part G compliance. Don’t waste precious time producing your own spreadsheets, simply download the free version now to see how easy it is to use. 

All calculations are automatically carried out by the spreadsheet, the premium version is available for professional presentation of your calculations. All versions include the Building Service Portal guidance notes for help completing the calculations.

Use the Building Services Heat Pump Assessment Calculator to assess the potential of replacing your gas boiler with a heat pump system. The calculator produces a report with advice of heat pump feasibility, size of equipment and estimated costs. Simply answer 10 simple questions and receive your free personalised report.

Also see our blog post articles, What is a heat pump? and heat pumps vs gas boilers.