Dormer Extension Plans

Plans for Dormer Extensions and Windows

Dormer extensions significantly increase the floor area and useable living space in your loft.

Since the 2008 relaxation and simplification of planning rules dormers now fall under what is known as Permitted Development Rights, and often require no Planning Permission.

This change makes it simpler and quicker to add a significant amount of space to your home. Building plans are still required for Building Regulations Approval - to ensure the extension is constructed properly. If you would like to know the options for your loft and our prices for loft plans and devlopment call us and ask for a quote.

We will visit and discuss your ideas and give you a guide price.

We can then survey your property to establishe the roof dimensions: height, width and length; the general condition and structural suitability of loft and roof for extension; the sources of utilities and the external house characteristics such as location of neighbouring properties.

New Minimum Height Rules

Lofts now need only reach the minimum height at the access and entry point to convert into a habitable room built to Building Regulations Approval. Height should be 1.8 m minimum at the edge of a stair with 1.9 m at the centre line if the ceiling is sloping.

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See page 7 of Approved Document Part K for diagram and explanation. The new regulations allow lofts with low ceilings to conform to standards - so you can significantly add to the value of you house and the uses you loft space can be put to - such as a child's bedroom.

A loft survey provides us with the information on which to give professional advice and guidance as to feasibility and scale of a project, and how existing property features and controls may affect loft plans and layout.

Dormer construction

We develop design plans that indicate the detailed dormer design, e.g. position of stairs, windows, structural features, internal supporting walls, power sources, and plumbing.

Architectural building plans are drawn from agreed design drawings and submitted for Building Regulations Approval.

Planning Permission

Many dormer extensions and windows now do not require Planning Permission applications, however some do, such as those that will exceed generous volume limits or face the highway. Planning is used to ensure dormers are built (from a council's viewpoint) in the right place (protecting amenity and environment in the public interest), to the correct size, layout, sitting and external appearance of your house.

Because dormers have a visual impactm, specific regulations govern their external appearance.

Many Councils require 'they are not out of character with the ... area'.

Dormers need to be in-character with the neighborhood and your property, so extensions and windows are designed to a style that generally blends with the existing look and feel of your home.

Double Dormer Extensions

Design plans specify the pitch of roof, building materials and style of window decoration.

Street facing windows generally have a higher visual impact, as they are more visible. Planning approval may be more difficult to obtain for dormers that extend both forwards and to the front of the roof.

The visual appearance of neighbourhoods is an important feature in property prices and preserving the original appearance of an area will be a part of the planning officer's consideration.

This is particularly true within conservation areas where permission is required even to insert skylights within a roof.

Dormer windows that will to face over neighbouring properties may have the potential of intrusion on privacy, and regulations generally require obscure-glazed.

Architectural Plans

Some dormer designs will be covered by many planning controls and regulations, particularly in Designated Areas such as Green Belt land and National Parks. Our experienced architectural and building plans service and advisory role can save you a significant amount of time and cost at this early stage.

Our specialist architectural surveyor will design your dormer using his professional construction experience to create the agreed designs.

We bring our expertise, understanding and experience into all project from the outset and guide you through the correct decision making process to arrive at the most suitable loft plans for your property.

When we understand your requirements, usage plans and the design ideas we can then introduce you to the most appropriate designs and materials, e.g.space saving stairs insulation and storage solutions.

Rear facing dormer

Many roof dormers require a small compromise between maximising living space and meeting Permitted Development Rights or having plans approved if contentious. Often rear facing dormers have a VELUX® skylight installed on the street facing side to avoid P.P.

Under the regulations that came into effect from 1 October 2008 a dormer loft conversion / roof extension is considered a permitted development, and generally does not require planning permission.

Permission is required though if you plan to extend or alter the roof space more than specified limits and conditions:

• Roof volume increase of 40 cubic metres terraced houses, or 50 cubic metres for detached and semi-detached houses (so 2-3 bedroom houses generally will be okay for dormers)
• No extension to go beyond the plane of the existing roof slope of the principal elevation that fronts the highway. (i.e. dormer are not to face the street)
• No extension to be higher than the highest part of the roof. (i.e. the dormer does not increase the roof height)
• Materials to be similar in appearance to the existing house. (i.e. keep it in keeping with house and street)
• No verandas, balconies or raised platforms. (i.e. no add-on's)
• Side-facing windows to be obscure-glazed; any opening to be 1.7 metres above the floor (i.e. neighbours need to maintain their privacy and there are safety requirements)
• Dormer extensions, excluding hip to gable dormers (chimney wall to roof edge), are set back, as far as practicable, at least 20cm from the eaves (2 rows of tiles or a row of slates), (i.e. for aesthetics, preventing a "3rd storey" appearance)
• Roof extensions not permitted development in designated areas, i.e. National Parks, ANOB, conservation areas, World Heritage Sites (i.e. keep the nicer places very closely managed)

The majority of loft conversions including those with quite large dormers do not now require Planning Permission as the development can be completed under Permitted Development Rights. As Building Regulations approval is always necessary when creating habitable areas accurate plans need to be drawn up for approval.

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