HomeMy WebLinkAbout2022-03-03 Diamond Bar Village Cannon Review.pdf
1050 Southwood Drive 210704
San Luis Obispo, CA 93401 1
T 805.544.7407
F 805.544.3863
CannonCorp.us
March 3, 2022
Raymond Tao, Building Official
City of Diamond Bar
Building and Safety Division
21810 Copley Drive
Diamond Bar, CA 91765
Subject: Diamond Bar Village Condominiums
Raymond,
This letter provides comments related to the structural repair package for The Village at Diamond Bar
Condominiums (aka Golden Springs Village) located at 23601 Golden Springs Drive, Diamond Bar,
California. The package was provided by Englekirk Structural Engineers and was dated February 2,
2022. I have reviewed the repair package in relation to the items I observed during my site walk on
November 21, 2021.
ENGLEKIRK REPAIR DRAWINGS:
The Englekirk repair set is divided into three sections: perimeter building elements, roof components,
and typical detailing for repairs.
Perimeter Building Elements:
In comparison with my notes, the specific repair list does not include the following items I identified
during my site visit:
· Building A:
o Unit 20 wing wall by entry – there is small hole that needs a stucco patch.
o Unit 15 wing wall by entry – there is an existing investigation patch that needs to
receive a stucco cover.
· Building B:
o Unit 6 end roof beam over wall – beam is badly decayed and should be replaced.
o Unit 7 end roof beam over wall – beam is badly decayed and should be replaced.
o Unit 8 end roof beam over wall – beam is badly decayed and should be replaced.
· Building C:
o Roof step between Units 8 and 9 – beams are badly decayed and should be
replaced.
· Building D:
o Unit 11 end roof beam over wall – beam is badly decayed and should be replaced.
· Buildings E, F, G, and H:
o No issues.
· Building I:
o Unit 10 roof over deck adjacent to wing wall – roof deck needs replacement.
· Buildings J and K:
o No Issues.
1050 Southwood Drive 210704
San Luis Obispo, CA 93401 2
T 805.544.7407
F 805.544.3863
CannonCorp.us
Roof Plans:
I examined the roof conditions of buildings C, D, G, and J. As noted in my prior report, I observed:
· The stucco caps at the parapets and wing walls are cracked and spalled at most locations
such that they allow rain intrusion into the tops of the walls.
· One noted condition was of a loose clay roof tile that had slid down over the top of the
adjacent tile below (at one of the building C mansards). It is unknown how common this
condition is.
· The interior side on some of the roof parapet walls have torn finishes or are entirely missing
finishes which provides a path for water absorption into the walls.
Wall Flashing Caps: The Englekirk plans indicated repairs to most of the walls that extend up past the
roof (and parapet walls) that were originally finished with stucco over the top of the wall. I observed
that many of the metal wall cap flashings that were added over time were in poor condition and
should be replaced. I recommend that all the flat stucco at the top of the walls (and parapets) at all
buildings have new integrated cap flashings that are appropriately attached, integrated with the wall
interior and exterior finishes, and sloped to drain.
Parapet Wall Finishes: The interior, non-stucco, wall finishes were not addressed by Englekirk. I
noted numerous locations where the inside face of the parapet walls finish was not stucco and the
finish material used was integrated into the roofing system. In several observed locations, the
material was torn or missing entirely. I recommend that the new parapet caps include a flashing
system compatible with a future roofing and parapet wall finish system.
Typical Roof Details:
I reviewed the Englekirk details shown on drawings SK-30 to SK-33 and offer the following:
o SK-30:
o Details 1 and 2: There is no mention of integrating flashing and building paper into the
repairs.
o SK-31:
o Detail 1:
o The fascia should be replaced with new pressure treated fascia.
o No diameter is indicated for the Titen HD screws at the base plate.
o Detail 2:
o All new wood should be pressure treated.
o The wall framing below the beams in these locations are very likely to have rotted
framing below. There should be a note regarding replacing all rotted wood with
pressure treated wood.
o SK-32:
o Detail 1:
o The edge distance between the 3x6 ledger and the screws indicated is very short
and likely to split the wood. I suggest maintaining a minimum 4” dimension
between the ends of the blocks and the connectors.
o Most likely there is blocking between the roof joists atop the wall top plate and
roof sheathing. That blocking would provide a better opportunity for connectors.
o See the attached optional support connection for consideration.
1050 Southwood Drive 210704
San Luis Obispo, CA 93401 3
T 805.544.7407
F 805.544.3863
CannonCorp.us
o Detail 2:
o This detail’s bolts at two-foot centers may transfer load into the added 4x10
beam, but there may not be enough bolts at the ends to transfer enough shear
back into the original beam for transfer into the wall (the added beam has no
shear transfer connectors to bypass the original beam). My observation was that
most wood decay occurred at the ends of the beams and that the original beams
may not have enough remaining shear capacity to transfer loads to their support
framing in the walls.
o SK-33
o Detail 1:
o No comments.
o Detail 2:
o No diameter is provided for the Titen HD anchors.
CLOSURE
It appears that the Englekirk drawings represent known structural repairs based on their observations.
They do not appear to have performed any destructive openings to check for further damage at
locations to identify additional work that may be necessary when finishes are removed, and
conditions exposed. Also, their repair details and notes do not provide specific information related to
integrating new finishes into existing finishes, directions for providing building paper or stucco system
components, or proper design and installation of metal flashings inherent to the original design. A
complete repair solution for the buildings is dependent on completely thought through building
envelope systems. I recommend that the HOA retain a building envelope expert for the needed level
of detailing to ensure that work is done correctly and the same conditions to not repeat themselves in
the future.
Sincerely,
Marshall Pihl, SE5101
Structural Director