Irrigation system installation
Do the crossings while the ground is open
Almost every irrigation problem we get asked about is really a crossing problem. Water has to get from the valves to the other side of the driveway, or under the front walk to the beds along the fence, and there is a finished paved surface in the way. Nobody wants to hear that the answer is opening it up.
Which is why we do the crossings at the base stage. While the excavation is open and the aggregate is going in, we lay sleeves under every driveway and walkway that irrigation might ever need to cross, cap the ends and mark them. Empty pipe is cheap. Once it is in, a line can be pulled through it any time, by us or by whoever does your planting, without lifting a single paver. If we are already rebuilding the driveway, this is the moment to sort it.
Exterior Designs is family owned and operated in San Carlos and our trade is pavers and natural stone. Irrigation comes in as part of that: the sleeves, the trenching while the ground is open, and the zone layout around the hardscape we are building. Ask for a free estimate and we will plan the crossings in.
Why do sleeves have to go in during the base stage?
Because that is the only time the ground under the paving is open and free. The excavation is already dug, the aggregate base is going in in lifts, and a length of pipe laid across it adds minutes to the day. We run the sleeve wider than the paving on both sides, cap it, and mark where the ends sit so nobody has to go looking. The base itself still goes in to the ICPI installation standard, compacted in lifts, sleeve or no sleeve.
Do it later and it is a different job. The pavers come up, the bedding sand is pulled back, a trench is cut through the compacted base, the pipe goes in, then the base is recompacted and the surface reset. Pavers are the one hard surface where that is even possible, and the same logic covers power and low voltage cable. It is all planned together with the landscaping side of the business.
What is a zone and why does it matter?
A zone is a group of outlets that run together off one valve. The reason to split a yard into several is simple: different areas want different amounts of water at different rates. A lawn in full sun and a shaded bed of shrubs on the same zone means one of them is always wrong, and usually it is both.
So the lawn gets its own zones, the beds get theirs, and anything in deep shade or on a slope gets separated out again. Slopes matter here, because on the hillier lots around Belmont and Hillsborough water runs off before it soaks in, so those zones want shorter cycles with a soak between them. A raised bed held by a retaining wall drains faster than flat ground and belongs on its own zone too.
Get the sleeves in before the paving closes
Free estimates in San Carlos and across the Peninsula. Every installation built to ICPI specification, 20 year warranty.
Call (650) 705-0628Drip or spray?
Both, in different places. Lawn takes spray, because you are watering a continuous surface and you need even coverage across all of it, with the heads placed so each one throws far enough to reach the next. Beds take drip, because you are watering individual plants and putting water at the root rather than over the leaves and the mulch.
Drip in beds also keeps water off the paving, which is worth more than it sounds. Spray that lands on a walkway or a wall face leaves mineral staining on the stone and keeps the joints damp, and damp joints grow things. So we set the heads and the bed edges at the same time we set out the whole yard's hard surfaces.
Where do the valves go?
Somewhere you can get at them. Valves live in boxes set flush in the ground, and they need to stay reachable, because a valve is the part that eventually needs a diaphragm or a solenoid. Buried under a new patio or lost under mulch, a routine fifteen minute repair turns into an excavation.
We put the boxes in planted areas or at the edge of the lawn, clear of the paving and clear of anywhere a car parks, with the lids sitting level with the finished grade so a mower rides over them. We also record where they are while we are still on site. The same rule covers the transformer when we run low voltage lighting cable through the same yard.
Ask a paver installer
Straight answers about paver installation on the Peninsula
When is the right time to do irrigation?
Before the hardscape goes down. Every crossing under a driveway or a walkway is close to free while the base is still open, and expensive once the paving has closed over it, so the sleeves go in while we are already there.
Can you add irrigation under a paved driveway later?
Yes. Pavers can be lifted and reset, so we open a run across the driveway, cut the base, place a sleeve, recompact and put the same stones back. It looks the same afterward. It just costs a day that a piece of pipe would have saved.
How many zones does a normal yard need?
It depends on the yard rather than its size. Sun and shade split it, lawn and beds split it again, and slopes split it once more. We would rather add a zone than have one area always over or under watered.
Will sprinklers spray onto my new paving?
Not if the heads are set properly. We keep spray off the stone, because water landing on pavers leaves mineral marks over time and keeps the joints damp. Beds along the paving go on drip for the same reason.
Do you handle the planting as well?
No. We build the hard surfaces and set up what runs under them. Plenty of customers have a gardener for the planting, and we leave the sleeves, the beds and the grades ready so that work is straightforward when it happens.
Do you work outside San Carlos?
Yes, right across the Peninsula and the wider Bay Area. San Mateo, Belmont, Redwood City, Burlingame, Hillsborough, Menlo Park and Atherton are all inside our normal working area, and we have worked in Foster City and Los Altos as well.