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Guardian Structural Technologies

The E3 mortgage savings programme

Energy-efficient mortgage programmes recognise that a house costing less to run leaves more income available to service a loan. Guardian publishes an E3 Quotient document on the subject.

The principle

Underwriting looks at what a borrower can afford each month. Utilities are part of that, but conventional underwriting treats them as an unknown. Energy-efficiency mortgage programmes bring the expected utility cost into the calculation, so a demonstrably efficient house can support a larger loan or a better ratio.

The mechanism differs by programme, and the documentation requirements are the practical barrier: the efficiency has to be demonstrated in a form the lender accepts.

What Guardian publishes

Guardian publishes the E3 Quotient for Build document alongside its energy-efficient components material, and lists environmental tax rebates among the builder benefits, noting that panels are PHIUS, LEED and Net Zero capable designs.

What Guardian publishes

  • Guardian publishes the E3 Quotient for Build document and refers to the E3 Mortgage Savings Program on the products page.

    Source · E3 Quotient for Build; Products page videos section

  • Environmental tax rebates: panels are Passive House Institute United States, LEED and Net Zero capable designs.

    Source · Differentiation sheet

Written by Data Subsystems, for Guardian Structural Technologies. Last updated .

Drafted from Guardian Structural product literature and published building-science sources. Awaiting Guardian technical review. Confirm any figure against the current product documents or ask us before you rely on it in a design.

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