The Paper has been written with the aim of providing advice for all parties involved in the process of designing and using calcium sulfate based screeds primarily for use with ceramic and natural stone tiling, and should be used in conjunction with current and forthcoming British, European and International Standards on tiles, tile related products and tile fixing. The guidance can also apply to other rigid tiles.
Table of Contents
1 Foreword
2 Definitions
3 Product description
3.1 …Uses
3.2 …Characteristics
3.3 …Materials
3.4 …Typical Physical Properties
3.5 …Product Recognition
4 Design considerations for screed
4.1 …Forms of Screed Construction
4.1.1 ……Bonded construction
4.1.2 ……Unbonded construction on a separating membrane
4.1.3 ……Floating construction – unheated
4.1.4 ……Floating construction incorporating underfloor heating
4.2 …Thickness
4.3 …Movement Accommodation
4.4 …Setting out of Tiling
5 Screed installation
5.1 …Surface Preparation
5.1.1 ……Bonded Screeds
5.1.2 ……Unbonded and Floating Screeds
5.2 …Application
6 Surface treatment, drying and testing of the screeds
6.1 …Surface Treatment
6.2 …Drying
6.3 …Testing
6.3.1 ……Residual Moisture Levels
6.3.2 ……Soundness Testing
6.3.3 ……Departure from datum
6.3.4 ……Surface Regularity Test
7 Joints in screed
7.1 …General
7.2 …Movement Joints
7.2.1 ……Movement joints in unheated calcium sulfate floor screeds
7.2.2 ……Movement joints in heated calcium sulfate floor screeds
7.3 …Intermediate or Stress Relieving Joints
7.3.1 ……Intermediate/stress relieving joints in ceramic tiling on unheated calcium sulfate floor screeds
7.3.2 ……Intermediate joints in heated floor structures
8 Surface preparation and repair of the screed
8.1 …General
8.2 …Surface Regularity
8.3 …Cracks
8.4 …Surface Damage
8.5 …Other Surface Defects
9 Tiling systems
9.1 …Assessment of Substrate
9.2 …Priming and Levelling
9.3 …Tanking on Pumped Calcium Sulfate Screeds
9.3.1 ……Background Information
9.3.2 ……Priming
9.3.3 ……Tanking
9.4 …Adhesive Selection
9.5 …Movement Joints in the Screed
9.5.1 ……General
9.5.2 ……Movement joints in the tiling and the screed
9.5.3 ……Ceramic Tile and Natural Stone Movement Joints
9.6 …Tile Installation
9.7 …Grout Selection
10 Cleaning & maintenance of tiles
11 Sources of reference/bibliography