subject: Cost implications for cladding systems [print this page] Cost is often a key question in a project, yet the impact and implications of it are often misconstrued. The simplest and most common comparisons of cost are based on capital cost, but it is important to note that the adoption of life-cycle costing can often reverse cost-based decisions.
The cost of the pre-finished steel is only a small part of the cost of an insulated cladding system, so changes in the pre-finished steel specification have a relatively small effect on the overall system cost.
Fire resistance
The fire performance requirements differ fundamentally from those relating to thermal performance, durability, weathertightness and acoustics in that fire is an exceptional event, from which it is usually unlikely that the building will survive in a serviceable state. Indeed, the purpose of the Building Regulations with respect to fire is to ensure the Health and Safety of the occupants and people close to the building, rather than to preserve the building.
External attachments
Examples of external attachments are:
Flashings
Although only a small component, it is often the flashings, which have the greatest impact on the overall appearance of a building. Paying close attention to detail in flashings can make a difference and deliver a well-executed building.
Rainwater goods
These goods consisting of gutters, outlets and downpipes, work in the fundamental role of drainage.
Penetrations
These are such things as vent pipes, air conditioning units or other small penetrations. With all openings, it is the early planning of opening positions, which allow the best detailing.
Lightning protection
In general, a building with metal roof and wall cladding will provide the best overall protection against lightning, especially when internal electronic equipment, which may be affected by the electromagnetic effects of lightning, is taken into account.
The main components of lightning protection systems are:
* Air terminations
* Down conductors
* Earth terminations
Design detailing
When detailing the building envelope, particular attention should be given to the avoidance of water and dirt traps by specifying suitable slopes and end laps. To ensure that the overall effect of detailing is positive, there are a few key principles which should be followed, such as:
Use welted edges on flashings to maintain straight edges.
All flashings should be fixed to a solid backing structure where possible.
To ensure airtightness, the use of fillers and mastics is important at all junctions.
It is always important to specify details accurately and ensure reputable, experienced contractors are used.
