Updated: May 09, 2026
Location and Projects
Address
P O BOX 2028, Issaquah, WA, 98027
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Cornerstone Const/seattle Construction
Since 1986, Cornerstone Construction of Seattle Inc. has specialized in earthwork and underground utility construction throughout the Greater Puget Sound region. Based in Issaquah, the company has collaborated for over three decades with a range of local general contractors and builders, including RAFN, Compass, Charter, Hammer and Hand, R. Thoreson Homes, Teak Construction, and Dyna Contracting. Projects typically involve excavation, grading, and the installation of underground utilities for both public and private developments. Cornerstone Construction has established a longstanding working relationship with the City of Seattle spanning more than 30 years. The team is experienced in managing complex regulatory requirements and coordinating with subcontractors on multifaceted construction projects.
Cornerstone Const/seattle Inc Services
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Cornerstone Const/seattle Inc Contact Information
Phone Number: (253) 918-5850
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Address: P O BOX 2028, Issaquah, WA 98027
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Building Permits by Cornerstone Const/seattle Inc
This is a sample of this contractor's permits. Click here to access their complete permit history.
Civil construction permit for madrona electric for installation of utilities (sewer stub stormwater) and landscaping
Valuation:
N/A
Permit #:
C20003906
Status:
complete
Fee:
$13,677
Permit Type:
N/A
Building Type:
N/A
Dustin ryland remodel addition alter. connect new downspout lines into existing underground downspout pipe. connect footing drains to existing cb. existing cb not mapped. approved drainage connection to existing side sewer or to storm. associated building permit 6621543-cn
Valuation:
$3,000
Permit #:
6700768-SS
Status:
complete
Fee:
$375
Permit Type:
Addition/alteration
Building Type:
Single family/duplex
Cut and cap the existing side sewer(s) at 4417 and 4423 and provide for 2 new side sewer connections and 1 storm connection tapped into the existing main. associated building permit 6608783-cn. 4-12-19 ksd: revised to a single connection to main per pe stamped plans and concurrence letter
Valuation:
N/A
Permit #:
6703355-SS
Status:
complete
Fee:
$2,093
Permit Type:
New
Building Type:
Multifamily
New sanitary to existing sanitary lateral pe evaluation & certification req'd. new drainage to ditch. assoc. building permit #6496483 3/21/18 msr: revised description to eliminate pe eval/cert requirement; ss stub installed in 2005 permit 6051090
Valuation:
N/A
Permit #:
6605844-SS
Status:
complete
Fee:
$1,707
Permit Type:
New
Building Type:
Single family/duplex
Restoration in right-of-way for new side sewers for 7-unit
Valuation:
N/A
Permit #:
ROW19-1026
Status:
final
Fee:
$1,592
Permit Type:
Sewer improvements
Building Type:
N/A
Frontage 11 lot subdivision of 11 townhome units in 2 bldgs
Valuation:
N/A
Permit #:
ROW19-0377
Status:
final
Fee:
$4,080
Permit Type:
Frontage improvem...
Building Type:
N/A
New sanitary and new drainage to new connection to combined main for assoc building permit 6542988. 6-5-18 ksd revision: ss to existing ss. connection may be 30 days from jun 1
Valuation:
N/A
Permit #:
6648804-SS
Status:
complete
Fee:
$2,228
Permit Type:
New
Building Type:
Single family/duplex
Frontage utilities landscaping wtr line restore-7-unit tw
Valuation:
N/A
Permit #:
ROW19-1023
Status:
final
Fee:
$10,991
Permit Type:
Frontage improvem...
Building Type:
N/A
New side sewer footing drains to ex. side sewer. drain to curb weep. line ex. sewer from property to within 2 of the main. pe eval req'd. assoc. building permit #6536537. pe eval received 10-12-17 ksd
Valuation:
N/A
Permit #:
6584896-SS
Status:
complete
Fee:
$1,913
Permit Type:
New
Building Type:
Multifamily
Frontage improvements for 7-unit townhome
Valuation:
N/A
Permit #:
ROW19-0467
Status:
final
Fee:
$5,373
Permit Type:
Frontage improvem...
Building Type:
N/A
Repair existing sewer line that has blockage or has collapsed. on site work only.revision to existing permit 6638824 to include work in row
Valuation:
N/A
Permit #:
6638824-SS
Status:
complete
Fee:
$476
Permit Type:
N/A
Building Type:
Multifamily
Repair existing sewer line. 5-22-18 ksd added drain add/alt to permit. 1/13/2020 rem: permit expiration date extended to 3/31/2020 to facilitate submittal of as-built drawing
Valuation:
N/A
Permit #:
6657378-SS
Status:
issued
Fee:
$756
Permit Type:
N/A
Building Type:
Single family/duplex
New sanitary to main in 30th ave s. 2 new storm connections; 1 to ex. & 2nd to the storm main in s mcclellan st. assoc. building permit #6532016. pe eval/cert. req'd
Valuation:
N/A
Permit #:
6595432-SS
Status:
complete
Fee:
$2,055
Permit Type:
New
Building Type:
Commercial
2 new connection for 7-unit townhome building
Valuation:
N/A
Permit #:
WWU19-1020
Status:
final
Fee:
$20,185
Permit Type:
New connection
Building Type:
N/A
Sewer work in row for 7-unit townhome building
Valuation:
N/A
Permit #:
ROW19-0469
Status:
complete
Fee:
$2,786
Permit Type:
Sewer improvements
Building Type:
N/A
Line existing side sewer on property to location where 8811 39th ave s and 8817 39th ave s come together
Valuation:
N/A
Permit #:
6650368-SS
Status:
complete
Fee:
$280
Permit Type:
N/A
Building Type:
Single family/duplex
New side sewer pipe on private property. new downspout connect to side sewer at property - all add/alt. assoc. building permit #6488922
Valuation:
N/A
Permit #:
6594938-SS
Status:
complete
Fee:
$946
Permit Type:
Addition/alteration
Building Type:
Single family/duplex
Frontage improvements utilities etc -7-unit townhome building
Valuation:
N/A
Permit #:
ROW18-2050
Status:
expired
Fee:
$12,397
Permit Type:
Frontage improvem...
Building Type:
N/A
Sewer core & main connections for 7-unit twinhome building
Valuation:
N/A
Permit #:
WWU19-0471
Status:
complete
Fee:
$300
Permit Type:
Core main
Building Type:
N/A
Storm and sewer installation and tie into existing service. 6-13-18 ksd added drainage pump
Valuation:
N/A
Permit #:
6639695-SS
Status:
complete
Fee:
$1,255
Permit Type:
Addition/alteration
Building Type:
Single family/duplex
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Cornerstone Const/seattle Inc License info
Verified License
| License # | CORNECI962RO |
| Status | Active |
| City | Tukwila |
| Type | Construction Contractor, General |
| Class | Corporation |
| Business Type | Corporation, Limited Liability Company |
- BuildZoom verified this license was active as of March 2026.
Verify this license's status for Cornerstone Const/seattle Inc at the The City of Tukwila, WA.
This is a sample of licensing data; click here to access a complete history.
Verified License
| License # | CORNECI962RO |
| Status | Active |
| State | Washington |
| Type | Construction Contractor, Construction Contractor |
| Business Type | Corporation, Limited Liability Company |
- BuildZoom verified this license was active as of May 2026.
Verify this license's status for Cornerstone Const/seattle Inc at the Washington State Department of Labor & Industries.
This is a sample of licensing data; click here to access a complete history.
Verified License
| License # | WA294 |
| Status | Active |
| State | Washington |
| Business Type | Corporation, Limited Liability Company |
- BuildZoom has not verified this license since June, 2015.
Verify this license's status for Cornerstone Const/seattle Inc at the Washington State Department of Labor & Industries.
This is a sample of licensing data; click here to access a complete history.
Inactive License
| License # | CORNEHL817PW |
| Status | Inactive |
| State | Washington |
| Type | Construction Contractor, Construction Contractor |
| Business Type | Corporation, Limited Liability Company |
- According to the Washington State Department of Labor & Industries, the status of this license was at one point cancelled. However, this information may have changed. If this is your business, please update your license status.
Check this license's status for Cornerstone Const/seattle Inc at the Washington State Department of Labor & Industries.
This is a sample of licensing data; click here to access a complete history.
Inactive License
| License # | CORNEHL924KM |
| Status | Inactive |
| State | Washington |
| Type | Construction Contractor |
| Business Type | Corporation, Limited Liability Company |
- According to the Washington State Department of Labor & Industries, the status of this license was at one point cancelled. However, this information may have changed. If this is your business, please update your license status.
Check this license's status for Cornerstone Const/seattle Inc at the Washington State Department of Labor & Industries.
This is a sample of licensing data; click here to access a complete history.
102
BuildZoom Score
Insured
| Insurer | United Specialty Insurance Com |
| Insured up to | $1,000,000 |
Bonded
| Bonded Agent | American States Insurance Co |
| Bond Value | $12,000 |
303
Permits
- Building permit records show that Cornerstone Const/seattle Inc has worked on 303 permitted projects.
Cornerstone Const/seattle Inc Employees
BR
Bonnie Ryland
Vice President
DR
Dustin Ryland
Member
JR
Joshua Ryland
Chief Executive Officer
KR
Keith Ryland
President
RJ
Ryland, Dustin John
Owner