A Practical Guide to Single Storey House Extensions

Andrew R. Williams

• Publisher: Routledge
• Year: 2003
• ISBN:
  9781135385293
• Edition: 1
• Topic: Architecture
• Subtopic: Architecture General

A guide to tackling the problems experienced in a project of this nature relevant to planning and building control procedures.

appendices

Appendix A

Most Councils issue guidelines for extensions to domestic properties in their area. I have indicated below atypical ‘Design Policy’ but this must not be taken as gospel. The policy may differ from Council to Council.

Note well

There is a basic anomaly in Planning in England and Wales which is that if your extension constitutes ‘Permitted Development’ then the Council has virtually no control over the design. In other words, generally speaking, Design Policies can only be enforced if you need planning approval.

It is quite possible to get a situation where a planning officer at a Council will not be able to approve your plans because it does not comply with the Council’s design policies if you apply for full planning permission but if your extension complies with all the parameters of Permitted Development then you can still build it. My advice is to check to see if you need planning permission first.

Typical design policy document

Domestic extensions generally

1. Harmonising—all materials should match as closely as possible those of the existing structure.
2. Overlooking Neighbours—no proposed windows should be close to the neighbour’s boundary.
3. Minimum distance to rear boundary—a rear extension must leave a minimum of 7.50 metres between the extension and rear boundary.
4. After construction of new extension—the rear garden should have remaining at least 50m2 of free space.
   

   Single storey extensions

5. Rear extensions adjacent to or directly on the party boundary—should not exceed 3.0 metres. An existing extension adjacent may allow an increase in depth to be considered.
6. Side extensions—these are acceptable provided that it does not preclude the provision of a garage/garage space behind the front most wall of the building.
7. As a general rule—any extension should not project beyond existing building lines.
   

   Two storey extensions

8. Terracing effect—side extensions will not be allowed if they create a terracing effect between two properties.
9. Flat roofs are not acceptable on two storey extensions unless the existing property has a flat roof.
10. On semi-detached property/terraced dwelling—two storey extensions adjacent to a boundary will in most cases not be considered acceptable.
    

    Dormer extensions

11. . Where a loft is converted a dormer will not be acceptable if the new construction projects above the ridge line of the existing property.
    

    Garages

12. Projection in front of the foremost part of the house—this will not usually be considered acceptable except where built in conjunction with front porch extension.
13. Where a garage is constructed it must have minimum dimensions externally of 5 metres and a width of 2.40 metres and there must be at least 5 metres left as driveway between the garage doors and the back of pavement line.
14. Unsightly bonding on front elevations—in order to avoid cutting bonding being visible on front elevations the garage must be set back at least 112mm where it is attached to the dwelling unless constructed in conjunction with a porch.
    

    Garage Conversions

15. Where it is proposed to convert an existing garage into habitable accommodation this will only be considered acceptable where a garage space of at least 5 metres x 2.40 metres is provided behind the foremost wall of the original dwelling.
    

    Porches

16. In most cases it will not be considered acceptable if the porch projects more than 1.50 metres from the foremost wall of the original dwelling.

Appendix B

Appendix C

COND1/AUGUST 1985

Appendix C
Notes regarding planning and building control procedure and conditions of engagement

(A) GENERALLY

In these conditions the words ‘I’ or ‘We’ or ‘Us’ means the surveyor or the practice of J Soap & Co.

The term ‘you’ or ‘your’ refers to the owner of the property or the person who has authorised the plans to be prepared.

The plans are purely for the use of you or your builder and is not for issued to third parties without permission and we will not be responsible for any alleged losses incurred should third parties act upon the details provided.

Normally (unless your house is listed or in a special area) the only approvals required when you build an extension are:

1. Planning Approval (or Class 1 Permitted Development);
2. Building Control approval.

Should Listed Building Approval etc be required this is an extra service. If your property is a listed building or in a special area or if there are tree preservation orders in force, it is essential that you let the Surveyor know during his visit so that he can make the necessary applications on your behalf. The responsibility for letting us know whether or not the property is listed or in a special area is your responsibility and no claims will be accepted at a later date if this information is not forthcoming. If you are in any doubt you must telephone your council and let us know as soon as possible.

DIMENSIONS ON THE DRAWING

Whilst every effort is made to ensure that the dimensions on the plan are accurate, errors can occur. As we are not a party to the contract between yourself and your future builder we make it a condition on our plans that your builder accurately checks all dimensions on site before starting work and before ordering materials.

This is specifically done so that we and you are protected against the possibility of an error getting through the checking procedure (see later for details).

We would stress that it is essential for you to insist that your builder carries out these checks before carrying out any work. Should the contractor need to make amendments you should tell the building control officer before carrying them out. We do not accept any claims for negligence or consequential loss with regard to incorrect dimensions shown on the plan as these could have been corrected, under the checking procedure, and the builder has been specifically instructed on the plans to check dimensions before proceeding.

FOUNDATION DETAILS

Dimensions given on foundations are only indicative for normal soil conditions. As trial holes have not been dug on site it is impossible for us to do otherwise unless advised by you that you know of bad ground in the area. If it is necessary to revise the foundations on site once the works commence this is not a defect on the plans and the plans specifically advise the builder to agree exact foundation details with the building control inspector. Should it be necessary to provide calculations or amend the drawings in the light of on site excavation this is an additional service and a charge will be made.

DRAINAGE DETAILS

All drainage shown on the plans is provisional and may require on site agreement with the building control officer.

(B) PLANNING APPROVAL/PERMITTED DEVELOPMENT

Normally planning permission is required for extensions to domestic property. However in certain specific circumstances formal planning permission is not required. When we are of the opinion that the development constitutes permitted development, our normal procedure is to forward a copy of the plan to the Local Authority and request a formal confirmation that the Proposals are Class 1 permitted development.

Should the Local Authority require a formal application we would notify you accordingly.

The advantages of Class 1 approval are:

1. There is no planning fee.
2. It normally takes less time.

At the present moment the normal planning fee is £33.00 for domestic extensions but fees increase year by year with inflation. Should the fee increase while your application is being submitted we will notify you accordingly.

(C) BUILDING CONTROL

Most house extensions require Building Control approval. N.B. The plans when prepared must not be acted upon until they have been approved in accordance with clause 13 and 11 (1)(b) of the Building Regulations 1985. Should the owner or builder commence work without the approvals they do so at their own risk.

The fee charges are on a sliding scale. At present the fee charges vary according to the size of the extension. The normal fee for small extensions is either £12.65 or £25.30 but the exact details for your extension will have to be calculated from the tables.

(D) DETAILS REQUIRED ON A PLAN

In order to be acceptable to the Local Authority your plans must have the following details:

1. Plans of Proposed and Existing at scales of min 1:100.
2. Elevations of Proposed and Existing at scales of min 1:100.
3. Sections through the property and at scales min 1:100.
4. Location plan These can sometimes be combined.
5. Block plan These can sometimes be combined.
6. Specification.

(E) TIME

Time is not the essence of the contract. Whilst approximate times are given below, once the documents are lodged with the council we are powerless to speed up the approvals although we do try to contact the individual surveyors at regular intervals in order to assist progress.

(F) APPLICATION TIME/MINIMUM TIME TO APPROVAL

See Table

(Both times exclude the length of time taken to prepare the plans.)

THESE APPLICATIONS ARE NORMALLY SUBMITTED AT THE SAME TIME.

(G) SERVICE

The normal services carried out on your behalf are the initial survey of the property, preparation of working drawings at scales 1:100 and 1:50 with sufficient detail and information for interpretation of the proposed works for submission to the Local Authorities and for issuing to building contractors to obtain tenders or quotations.

(H) BOUNDARIES

We prepare the plans based upon dimensions taken on site. Where there are no obvious boundaries or they are hidden from view by debris, snow or existing buildings, we will agree the dimensions with you. Where fences and walls exist between properties we accept these ‘natural boundaries’ as being correct.

If you have any doubt regarding the ownership of any land we would advise you to s...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• Introduction
• Building construction
• Matching materials
• Building regulations
• Single stack system
• Kitchen planning
• Trees and other obstructions
• Drawing the plan
• Planning and building control
• Meeting the client
• Submitting plans
• Appendices
• recommended books