Changes

[[File:Bedding-raking.JPG|300px|thumb|right|Bedding course being spread across the infiltration area.]]

[[File:Bedding-raking.JPG|450px|thumb|right|Bedding course being spread across the infiltration area. (Photo Source: CVC, 2012)]]

The bedding layer consists of a coarse stone and provides a level medium onto which paved surfaces are installed. Note that bedding layers are required for permeable pavers but not porous concrete. Additionally, the bedding layer can function as the choker course, depending on the design.

The bedding layer consists of a coarse stone and provides a level medium onto which paved surfaces are installed. Note that bedding layers are required for permeable pavers but not porous concrete. Additionally, the bedding layer can function as the [[choker layer]], depending on the design.

Construction Steps:

'''Construction Steps:'''

#Place stone bedding material on top of compacted reservoir course.  

#Place stone bedding material on top of compacted reservoir course.  

#Level aggregate to the appropriate depth, as per the design. A vibratory screed can be used to level the bedding material.

#Level aggregate to the appropriate depth, as per the design. A vibratory screed can be used to level the bedding material.

Key Inspection Points:

'''Key Inspection Points:'''

*Granular bedding material is correct size and material (e.g. 5 mm stone) upon arrival to site. For an example of a municipal standard for gradation and material size, refer to Toronto Standard 861.

*Granular bedding material is correct size and material (e.g. 5 mm stone) upon arrival to site. For an example of a municipal standard for gradation and material size, refer to ([https://www.toronto.ca/wp-content/uploads/2021/08/952c-ecs-specs-gi-specs-TS861Sep2021.pdf City of Toronto, 2021])<ref>City of Toronto. 2021. TS 861 Construction Specifications for Permeable Interlocking Concrete Pavers. https://www.toronto.ca/wp-content/uploads/2021/08/952c-ecs-specs-gi-specs-TS861Sep2021.pdf</ref>.

*Bedding depth conforms to design and is uniform across the LID feature.

*Bedding depth conforms to design and is uniform across the LID feature.

*When a 3-metre straightedge is placed on the surface of the bedding material, gaps between the straightedge and bedding surface are not greater than 10 mm at any point.

*When a 3-metre straightedge is placed on the surface of the bedding material, gaps between the straightedge and bedding surface are not greater than 10 mm at any point.

Mistakes to Avoid:

'''Mistakes to Avoid:'''

*Fines in the aggregate – ensure that the correct stone gradation is provided and the medium is free of fines and crushed stone.

*Fines in the aggregate – ensure that the correct stone gradation is provided and the medium is free of fines and crushed stone. See [[Jar test]] to ensure there are no fines in the crushed stone aggregate.

*Compaction – the bedding layer cannot be compacted

*Compaction – the bedding layer cannot be compacted

*Use of plate vibrators – do not use plate vibrators for levelling, as they can crush the bedding material. Tamping should be performed after the installation of the pavers.

*Use of plate vibrators – do not use plate vibrators for levelling, as they can crush the bedding material. Tamping should be performed after the installation of the pavers.