EWI to New Manchester Window

Detail for a triple glazed replacement Manchester window and associated junction with EWI to wall above. Designed to help preserve the character of an existing Manchester window while reducing thermal bridging and improving air-tightness.

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EWI insulation with new window.

This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading the structural load of new window on EWI, and maximising glazed area.

The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required). This detail is designed with the intention that the window and box be installed prior to the external wall insulation system.

Target values: Thermal Performance (overall u-value) : 0.79W/m2K. Cill Psi value: 0.066 W/mK Lintel Psi Value: 0.00023W/mK

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EWI insulation with new window (Plan)

Detail for a new window with a timber frame, to be mounted into external wall insulation, in place of an existing window. This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading structural load of new window and maximising glazed area.

The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required). This detail is designed with the intention that the window and box be installed prior to the external wall insulation system.

Target values: Thermal Performance (overall u-value) : 0.79W/m2K. Cill Psi value: 0.066 W/mK Lintel Psi Value: 0.00023W/mK

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New window to EWI, retrofit installation

Detail for a new window with a timber frame, to be mounted into external wall insulation, in place of an existing window. This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading the structural load of new window on the EWI, and maximising glazed area.

The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required). This detail is designed so that the window and box can be installed after the external wall insulation system is in place.

Target values: Cill Psi value: 0.045 W/mK. Lintel Psi value: 0.059 W/mK.

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New window to EWI, for single brick reveal (section)

Detail for a new window with a timber frame, to be mounted into external wall insulation, in place of an existing window. Used where a single brick reveal means the original window was originally sat behind, and larger than, a structural opening in the outer face of an existing masonry wall.

This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading structural load of new window and maximising glazed area. The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required).

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New window to EWI, for single brick reveal. (plan)

Detail for a new window with a timber frame, to be mounted into external wall insulation, in place of an existing window. Used where a single brick reveal means the original window was originally sat behind, and larger than, a structural opening in the outer face of an existing masonry wall.

This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading structural load of new window and maximising glazed area. The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required).

View in conjunction with Section detail: "New window to EWI, for single brick reveal (section)"

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New window to EWI, for single brick reveal, retrofitted

Detail for a new window with a timber frame, to be mounted into external wall insulation, in place of an existing window; in this case: retrofitted from the outside after the insulation is installed.

Used where a single brick reveal means the original window was originally sat behind, and larger than, a structural opening in the outer face of an existing masonry wall.

This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading structural load of new window and maximising glazed area. The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required).

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Options for new window to EWI, for single brick reveal, retrofit

To be read in conjunction with: "New window to EWI, for single brick reveal, retrofitted" (or EW01-W-RP-FR).Two alternative options for new window installation to a single brick reveal; with either no subframe or reveal; or with a timber studframe support and stainless steel reveal.

Used where a Victorian single brick reveal means the original window was originally sat behind, and larger than, a structural opening in the outer face of an existing masonry wall.

This detail is designed to reduce thermal bridging and improve air-tightness whilst spreading structural load of new window and maximising glazed area. The timber box also acts as self-finished internal reveal. (May be painted/ varnished as required).

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New window to EWI, reduced width due to corner (Plan)

Detail for new replacement window, fitted into external wall insulation, where the existing window is fitted to an external corner, and requires a reveal box with a reduced width .

A variation on the "New window to EWI, retrofit installation" detail where the new window is mounted onto a timber box and installed into a finished EWI installation. This detail modifies the box design to allow for the corner detail shown.

Target Values: Cill Psi value: 0.045 W/mK Lintel Psi value: 0.059 W/mK.

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Retained window to EWI, with sloping cill

Detail for external wall insulation to an existing window, to be retained, with an existing sloping cill.This detail allows for the profile of the sloping cill to be retained whilst improving the thermal efficiency of the building envelope by allowing insulation to be carried up to the window frame underneath the tiled cill. Used in instances where the original window jamb is reduced in depth.

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Retained window to EWI, thin jamb (section)

Detail for external wall insulation to an existing window to be retained, where the existing window sits up against the inside edge of existing window jamb. This detail proposes phenolic foam to be used where the existing window jamb and head is too narrow for standard 40mm woodfibre reveal boards.

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Retained window to EWI, thin jamb (Plan)

Detail for external wall insulation to an existing window to be retained, where the existing window sits up against the inside edge of existing window jamb. This detail proposes Aerogel insulation to be used where the existing window jamb and head is too narrow for standard 40mm woodfibre reveal boards.

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EWI to existing window, retained, with secondary glazing install

EWI detail to head and jamb of an existing window (single glazed or other) where a a secondary double glazed window unit is to be added to the inside face of the window for improved thermal performance.

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