This client in Cambridge had an existing on grade deck around half of their pool patio. This deck was falling apart and creating a lot of problems for them. There were holes on the deck and it presented a lot of tripping hazards. So they wanted to replace it with a paver patio. We chose a small three piece pattern paver with border stones around the existing concrete and far side of the patio that allowed us to curve appropriately.
We began by tearing out the deck in disposing of it followed by an excavation around the entire area to a depth of at least 10 inches. This gives us room for a minimum of 6 in base material using a 3/4 in clean clear Stone that allows for the free flow water through the system. That way our base is not holding on to water which can cause movement, washout, and with freeze thaw Cycles the heaving of our pavers. We compact our subsoil and then lay our nonwoven geotextile on top of our subsoil to separate the base material from our subsoil. We then lay our base material in and compact it. We also lay a layer of biaxial geogrid this helps to stabilize our base material by interlocking the aggregates into the openings of the geogrid. We then screed a layer of HPB or High Performance Bedding. This is a 1/4 inch clean chip Stone water while allowing us to lay our pavers on top of a finer chip for leveling.
Along the back of the fence we needed to build a small one foot retaining wall. This is because we cannot lay pavers to the fence where the pavers will be higher than the base of the fence. The fence will not retain our base material so we needed a retaining wall to be able to retain our base material. Our retaining wall gets a 6 inches of base material with 6 inches of that retaining wall embedded.
We can then start to lay our pavers starting in a corner that is square so we started in the back left corner of this project. We did not start closer to where the front of the house is where we normally do because these will all get cut in a curve. These pavers get laid in a random pattern. We then lay our border pavers along the concrete as well as along the sides and we mark our cuts on top of the existing laid pavers. With our cuts marked we then cut all along our marked areas and also cut a curve going along the existing paver patio so that we can blend these two areas together nicely. Our pavers are installed with a 1/8 of an inch per foot slope away from the pool and two drainage areas. That way water is not sloping towards the pool.
It was not in our client’s budget to do a complete tear out of the existing paver patio we wanted to just be able to replace the deck and create a safe space for our client. With our borders installed everywhere we can then install an edge restraint to prevent the horizontal movement of our pavers. Along the one side of the fence we cannot completely lay our pavers to the fence otherwise those pavers will not have an edge restraint and they will move horizontally and settle over time. We always want 6 inches of that base material extended where possible. What we do there is we dress up the area with a black granite crushed stone on top of our registry to dress up the area. The edge restraint we installed is a concrete edge restraint that works well with our open graded base.
With our pavers installed we can then install our caps on top of the wall and we calculate appropriately the height and the slope of our pavers to the height of our retaining wall caps. We typically install a natural stone cap for our retaining walls because natural stone if it chips will always show natural stone whereas concrete caps if they chip will show an exposed aggregate.
We then install a polymeric sand jointing compound. This is swept through the joints and then compacted using a compactor with a protective mat below it so that our pavers do not get scratched and scuffed. This is an important step in the installation process so that the jointing compound goes to the bottom of our joint. Failure to do so will cause the polymeric sand to also fail. This is because there will be air pockets in that polymeric sand and eventual erosion of that polymeric sand. We also install the polymeric sand to 1/8 of an inch below the top of the pavers to ensure its success. Once we have achieved that we then blow off the surface to remove any polymeric sand dust or granules on the surface of the pavers so that we do not activate it and discolor our pavers. We then activate the polymeric sand using water and following the manufacturer’s instructions.
And this is our final result of our pool patio project.
Materials Used:
Techo-Bloc Eva Slate Shale Grey