On the smallest of schemes, annotated details may be all that is necessary and putting specification and drawing together may also assist the contractor.
However, on larger projects there is a danger that the specification will become dispersed onto several drawings, with repetition and contradictions creeping in. To avoid this, it is recommended that all the specification is found in one place. The drawn details can then linked to the appropriate specification description by systematic cross referencing, using the specifications own clause numbers.
This then leaves the question of the more general information such as the quality of topsoil or the strength of mortar? It is rarely adequate to leave such details to the expertise and discretion of the chosen contractor. In order to provide a professional service to your client, it often requires at least a few pages of specification separate from the drawings attached to the planting schedules, or the letter of invitation to tender.
An imperfect solution
I have touched on some of the obstacles which confront the designer and the contractor when faced with agreeing and achieving the desired standards on site;
- the need for reasonable financial certainty without being too restrictive,
- the huge amount of technical and contractual knowledge required;
- the designers’ time needed to tie up the more important loose ends,
- the absence of a simple appropriate standard form of contract.
Using an identical specification on every project, is therefore not only inappropriate, but may also be dangerous.
The concept of a ‘model’ specification is rather different from a standard solution because, the ‘model’ specification is designed to be edited by the designer to remove all extraneous information and to insert any additional information the particular project requires. The result is a tailor made document which should help the contractor.
Producing a project specification takes time and eats into the fee but the time is reduced with practice. No specification can be totally comprehensive. The designer’s decision on what to put in and what to leave out is a matter of judgement. That judgement will be made based on several factors such as the complexity of the project, the known competence of the contractor and whether the designer will be visiting site during the construction phase. Specification writing tries to be exact but in practice is an imprecise art.
A ‘model’ specification
The essentials of a ‘model’ specification are three-fold:
First it provides a familiar ‘structure’ within which every subject has its logical place.
Finding the appropriate instructions becomes quicker and easier because of this.
Secondly it can provide a check list of subjects which may need the designer’s attention. The designer can decide either to delete the subject as inappropriate or to include it with or without amendment.
Finally, by offering the designer a model clause the designer has guidance on written style and technical content.
I am sure that many designers have heard of the NBS Landscape Specification or the more modest publication “Specification Writing for Garden Design”(2) These model specifications can provide help and much needed technical guidance for the hard pressed Garden Designer. Writing a specification from scratch is a very daunting task; using a model specification makes that task considerably easier.
Even the best project specification and drawings in the world will not produce high quality work from a poor contractor. Things are less likely to go wrong with a good contractor. So every designer’s priority should be to assemble a list of good local contractors.
Then, provide them with all that essential specification information in writing by one means or another so that a proper price is tendered. Things are less likely to go wrong if the contractor has tendered a realistic price and is in possession of all the relevant information from the start. If things do go wrong, you and your client are better protected if the required quality is defined clearly and concisely.
