Slab foundation building in Bothell WA - a floor that fits your lot and your plans
Building on a new lot and unsure which foundation suits it? We plan the ground, forms and grade so your house sits on solid concrete.
- Licensed and insured.
- Free estimates at your property.
- We reply within 1 business day.
What goes into building a slab foundation in Bothell?
Slab foundation building in Bothell, WA, means pouring a concrete floor whose edges are thickened into the footing that carries your house, which needs the least digging of any foundation and leaves no floor framing to rot.
Most people who call about a slab are building a house, an addition or a shop on a lot they've just bought, and the first question is which kind of foundation the lot will take. The price moves with the size of the footprint, how much the ground slopes, how much digging and base work it needs and which slab type you choose. The schedule mostly turns on the city's permit file, any soils work and the weather on pour day. I'll give you a written estimate that spells out what's included and what isn't, so you can see where your own figure comes from.
How do you know your lot needs careful slab planning?
The lot slopes
If one side of the lot sits noticeably higher than the other, a flat slab poured straight on the dirt would leave the floor low at one end or buried at the other. That usually points to a stem-wall slab or a crawl space, and finding out after the forms are set means tearing them out and paying for the setup twice.
Water sits after rain
Puddles that hang around for a day or more tell me the water has nowhere to go, and a slab dropped into that spot will be sitting in it every winter. Planning the grade and drains now costs far less than chasing a damp floor once the house is framed.
Soft or filled ground
If your boots sink in, or you know the lot was built up with fill, the ground under a slab can keep settling after the pour. That ground has to be dug out and packed before any concrete goes in, because cracks and a dipping floor are much harder to deal with once walls sit on top.
How we handle slab foundation building
Before anything else, I'll help you choose between a one-pour slab, a stem-wall slab or a crawl space, based on your lot and how you plan to use the house later. Then our crew digs out to firm ground and packs the subgrade, the soil and gravel the slab sits on, because a base that's only raked level will settle along with the loose dirt under it. We set the forms, place the rebar, the steel that ties the slab together and keeps cracks from spreading, and shape the ground so water runs away from the house instead of toward it. I check the forms and grade carefully ahead of pour day, since neither can be fixed once the truck is here, and we time the pour to stay out of the midday heat that can leave a weak, dusty top. After the pour we finish the surface and let it cure, which is the wait while the concrete gains its strength, before anyone builds on it. If the budget gets tight, I'd much rather you save on something you can change later than on the base, because nobody sees the base on day one and it's the one part you can't redo.
A slab isn't the right answer for every house, and when your plans call for a different footing or wall, we also do foundation installation. For builders and small property owners putting a shop or commercial building on a slab, we handle concrete parking lot building too, so the grading for both is planned together.
One-pour slab
As a general rule, this suits a level lot in a mild climate, because the footing and floor go in at once and it takes the least labor of the slab types. The catch is that it sits close to the ground, so it leaves little room to work with a slope.
Stem-wall slab
This suits a sloped lot or a house where you want the floor raised above the ground, because a short wall goes on the footing before the floor is poured. It takes three steps instead of one, which adds labor, but on a sloped lot it usually fits far better.
Get a written estimate for your slab foundation
Send the form and we'll reply within one business day to set up a visit. I'll come out, look at your lot and write you a free estimate, with no pressure to book.
- Based in
- Bothell, WA 98011
- Hours
- Mon–Fri: 8 AM–11 PM, Sat–Sun: 7 AM–11 PM
What happens after you call about a slab foundation in Bothell?
Here's how a slab foundation job runs with us, from your first call to the walk-through at the end.
Call or send the form
Phone (425) 384-1147 or use the form, and we'll get back to you to set up a visit at your lot. Tell us roughly what you're building so we can plan the time we need.
I walk your lot with you
I come out, look at the site and ask what the house needs to do, now and later. You get a written estimate that spells out what's included and what isn't, so there's no guessing about what you're paying for.
We sort permits and set a date
We work through any permit questions with you, and when the city needs a permit we plan the start date around it. Once that's settled, the pour goes on the calendar.
Our crew builds and walks it
Our own crew does the work and I lead it on site, from the dig-out through the pour. When it's done, we walk the finished slab with you.
Why Bothell homeowners call C&S Bothell Concrete Contractors for slab foundations
I write your estimate myself
I come out to look at the lot and write the estimate myself, and I lead our own crew on site. The person who planned the job with you is the one standing there while it's built.
In business since 2017
I left a desk job to learn concrete on flatwork and foundation crews around here, and I started this business in 2017. That's nine years of slabs, steps and driveways where the ground prep came before the pour.
Licensed and insured, easy to check
We're licensed and insured. Washington requires every construction contractor to register with the Department of Labor & Industries, and a registered business shows up in the state's online lookup, so you can check us or anyone else before you sign.
On a slab foundation, the type you choose and the ground under it matter more than anything you'll see on top, so it's worth settling both before your plans are final. Please request an estimate or call (425) 384-1147 when you're ready.
Slab foundations, drains and site prep in Bothell
Bothell takes every permit and land use application online, through the city's permit center at MyBuildingPermit.com, and for a new house the site plan has to show the footing drain and roof drain. The city's checklist also calls for a soils report from a licensed geotechnical engineer, unless good data from the lots around yours shows one isn't needed. If your lot is in an erosion or landslide hazard area, the city allows only work that's been approved and permitted under an approved critical areas report. Any of these can change the slab type, the drains and the start date, so I look at the permit side when I come out for the estimate, and when a permit is needed we can prepare and file it with the city and plan the start around it.
The city's code puts the frost line at 12 inches with a moderate weathering rating, which tells us how deep the thickened edge has to reach and that the concrete will see some freezing and thawing. Most lots we see here stay wet through the winter, so the drains and grade get as much attention as the pour, and we plan the same way on jobs in Kirkland and Woodinville.
Questions about slab foundations in Bothell
Is a slab or a crawl space better for my lot in Bothell?
A slab usually suits a lot where you want the simpler build and no space under the floor to trap moisture, and a crawl space suits a house where you expect to change plumbing or wiring later. That's the general guidance across the country, and the trade-off is that a crawl space gives you room to work underneath but has to be sealed against moisture and pests. When I walk your lot, I'll tell you which way I'd lean and why.
Can I add plumbing to a slab foundation later?
You can, but because the pipes in a slab are cast into the concrete, adding or moving them later means cutting through the floor. We do concrete cutting when it's needed, though it's far easier to settle where the drains and lines go before the pour.
Can a slab foundation be poured in cold weather in Bothell?
Yes, a slab can be poured in cold weather as long as there's a plan to protect the fresh concrete. The concrete industry's guide treats it as cold weather when the air falls, or is expected to fall, below 40°F during the time the concrete needs protecting. We'll go over the forecast and the pour date with you before anything is scheduled.
How much does a slab foundation cost near Bothell?
A slab foundation in the Seattle area usually costs about $8 to $17 per square foot installed, and that's the going rate in the area, not our price. Your written estimate shows where your own job falls once I've seen the lot.
How do I keep water away from a new slab foundation?
Grade the ground so it falls away from the house on every side, and give the water a way out through footing drains and roof drains. Those are the same drains the city wants on your site plan, and we shape the grade to work with them before the slab goes in.
What should I have ready before I call about a slab foundation?
Have the lot address, what you're planning to build and any soils report or house plans you already have. That lets me spend the visit on the questions that matter for your slab instead of starting from scratch.
Related foundation and concrete work we build
Foundation installation
When your house plans call for a crawl space or a raised floor instead of a slab, this is the foundation work that carries the walls and frame.
Concrete parking lot building
Builders and small property owners putting up a shop or office often need parking beside it, graded and poured so water drains away from the new building.
Service areas around Bothell for slab foundations
C&S Bothell Concrete Contractors is based in Bothell, Washington, and builds slabs across the cities around it, including Kenmore and Shoreline. The 12 cities below each have their own page, and if you're not sure we come out your way, just ask.
Plan your slab foundation before the pour
Call (425) 384-1147 or send the form now, and we'll look at your lot while your house plans can still change to suit it.