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JMF provides several key tools to support both specifiers and manufacturers with compliance and design, including our online engineering calculator, our R-value calculation spreadsheet and our door weight calculator.
Use our door weight calculators to estimate the weight of timber doors based on dimensions and timber species. Accurate weight calculations are essential for selecting appropriate hardware and ensuring compliance with NZS 4211.
This calculator is readily available for all users, no login required!
We also offer a spreadsheet tool for calculating individual R-values for items of JMF joinery, to satisfy H1 Thermal Performance requirements.
For Manufacturers:
This tool is available on request – just email sarah@jmfnz.co.nz and we’ll send it directly to you.
For Specifiers:
Because factors like glass selection and configuration impact the R-value, we recommend contacting the nominated JMF manufacturer for your project to obtain accurate R-value data.
If a joiner has not yet been nominated, and R-values are required for building consent, JMF can provide indicative values. Please fill out the form below to request these details.
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