Choices to Consider
The depth and type of screed, the construction tolerances, and the provision of falls are all important design considerations for a successful installation. Milestone are experienced in assessing existing substrates and promote awareness regarding cure times and drying out moisture in screed. This may be important if the project requires a short programme to reduce the impact of closure of business.
The purpose of the floor and type of traffic upon it will influence choices such as slip, abrasion, and impact resistance, appearance and maintenance, and location of movement joints.
Levels and flatness are important when designing falls for effective drainage or access ramps. Milestone Flooring are a one stop shop that can supply a quality turnkey service which cover the entire needs of a flooring installation project.
Technical Aspects when Considering Design
Application recommendations are a minimum thickness of 5mm if bonded, 30mm if unbonded, or 35mm if a floating finish is required depending on material usage. Bonded screeds should therefore be thin, normally less than 50mm. Unbonded screeds should be thick, normally 70mm or more, and 100mm or more if curling must be avoided.
BS 8203 estimates the drying time for a sand cement screed as one day for each millimetre of screed thickness up to 50mm thick. This is dependent on the environment, warm and well-ventilated drying conditions are favourable, with thicker substrates or cold temperatures requiring additional time.
A screed joint must be formed above all structural movement joints, for heated screeds it is important to remember to place joints at door thresholds, to avoid thermal movement cracking.
The bond between the screed and substrate may fail if the screed is too thick, or an unbonded screed may fail if it is too thin. Screeds may lift or curl caused by differential shrinkage, un-bond, or fail to prevent disproportionate collapse and the development of composite action with the concrete slab below.
It is important that your investment is beneficial to your business in that the flooring you chose is what your business will stand on. There is no room for error, flooring being fit for purpose and technically sound is vital which is why Milestone Flooring are proud to be a trusted name in our industry to provide a quality seamless service.