Star Bolts...They Aren't Just Decoration!

By
Home Inspector with Sherlock Homes Inspections
http://actvra.in/4ZRp

You’ve probably seen these cool metal stars on old brick houses and thought they were just a quaint decoration.  The truth is that they are often much more than that.

Bulging or bowing in brick walls is common throughout the Philadelphia region, especially on 3 story rowhomes.  Star bolts are one less-expensive way to avoid completely rebuilding the wall.

Our problem starts in the mortar used to hold the bricks together.

Unlike more modern mortar (Portland cement mixtures), the lime mortar that was used pre-1920 (or so) is subject to dissolving when contacted by moisture or water, weakening the mortar and losing both compressive strength and bond strength. Foundation subsidence may also be found to blame.

Star bolts can be used to effectively re-secure loose or bowing wall back to the original state.   These metal stars are often seen on historic homes throughout the area, and are functional, not decorative (although they are attractive and interesting features).

Through the use of a grid work of 2 x 8 planks, backed by 4 x 4 posts, cables, and anchors, bulges of up to 3 inches can be reduced to less than an inch.  Removal of old lime mortar between the inner and outer courses of brick (called “wythes”) is needed to further reduce the gap to plumb.

The 10" diameter "star" plates are installed on ¾” threaded rods, and anchored anywhere from 4 to 8 joists deep in the home (this can require removal of flooring or ceilings).  These rods are fastened in place with washers and nuts and solid bridging (blocking) is installed between the joists. This combines the strength of the joists; essentially producing a 12x10 frame (for 4 joists) to resist brick movement, and allowing the star bolts to secure the exterior bricks in place.

Finally, the bolts may be round, oval, square, diamond, or star shaped. They should be at least 1/4" plate, and at least large enough to hold directly against at least 6 or 8 bricks. Those bricks than apply drag to other bricks around them.   A 20 foot wide house face will usually require 3 bolts per floor.

When properly installed, these bolts prevent the brick facing from sagging toward the street. The framing and flooring create a structural anchor, meaning that the bricks can't move without dragging the framing out into the street.

The cost for replacement of a brick wall can exceed $8000 - Star bolts typically cost approximately $1000 each. So, not only are they functional, they are also fiscally responsible!

Star bolting has been proven for over 100 years (either as original design, or as retrofit) to maintain structural integrity.  While fewer and fewer masons want to install them (they make more replacing the wall), they are a great solution to a common problem.

Posted by

Handwritten Signature

Philadelphia Home InspectionSherlock Homes Inspections 

Philadelphia's Top Rated Inspector

www.SherlockHI.com

Come on - be Social!! 

www.facebook.com/SherlockHomesInspectionsSherlock Homes Inspectons on Twitter

close

This entry hasn't been re-blogged:

Re-Blogged By Re-Blogged At
Groups:
Realtors®
Pennsylvania Professionals
Ask the Home Inspector
Philadelphia, PA
Almost Anything Goes
Tags:
philadelphia home inspection
star bolts
brick home repair

Post a Comment
Spam prevention
Spam prevention
Show All Comments
Rainer
235,608
Carla Morin
Brookfield - Peoria, AZ

What great information.  I would never have suspected it was anything but a pretty decoration.  I don't think I've ever seen anything like in in the Phoenix area but it's a pretty way to fix a problem.

Feb 08, 2011 03:55 PM #29
Rainer
40,460
Howard Wilson
Wilson Than Real Estate - Santa Monica, CA

If only the bolting plates used here in Southern California were as attractive! Thank you for the well-presented information and great photos, Joseph.

Feb 08, 2011 04:19 PM #30
Rainmaker
779,040
Evelyn Kennedy
Alain Pinel Realtors - Alameda, CA
Alameda, Real Estate, Alameda, CA

Joseph:

Being a Californian, I see those bolts alot.  But I have never seen a star bolt, usually they are round.  In Alameda, CA a retrofit of a mortar building has to uses those bolts.

Feb 08, 2011 04:27 PM #31
Rainmaker
411,434
Paula Hathaway, REALTOR, Sr. LBA,
Douglas Elliman Real Estate - Southampton, NY
...Finding Your Place In The sun!

What a terrific post---I have seen these in buildings in New York and other places like Boston and often wondered what ever possessed the owners to decorate their houses like that--now I see, and I like them too.! It is Form following function as steven Graham says!

Feb 08, 2011 04:31 PM #32
Rainer
248,359
Bill Pohl
Tetra Homes, Inc. - Loveland, OH

Thanks for the information. It is something that I didn't know but certainly makes sense.

Feb 08, 2011 04:42 PM #33
Rainmaker
83,017
Chris Eckert
Keller Williams Realty - San Mateo, CA
Your Mid-Peninsula Realtor
Interesting post. I forgot how many unreinforced masonry buildings we have on the San Francisco Peninsula
Feb 08, 2011 04:42 PM #34
Rainmaker
573,900
Brin Realty Associates Team At Bean Group
Bean Group | Brin Realty Associates - Amherst, NH
Amherst NH homes and Southern NH real estate

I learned something new early this morning...thanks I didn't know that was their purpose!  thanks.

Feb 08, 2011 09:20 PM #35
Rainer
251,119
A1 Certified Home Inspections
Lake City, FL

I never even gave them a second thought. Now I know. I wonder why this was never mentioned in my Home Inspection classes?

Feb 08, 2011 11:49 PM #36
Rainmaker
1,225,720
Michael Setunsky
Woodbridge, VA
Your Commercial Real Estate Link to Northern VA

Joseph, I would have guessed they were there for decorative purposes. Learned something new today. Thanks.

Feb 09, 2011 01:11 AM #37
Rainmaker
365,796
Ilyce Glink
Think Glink Media - Chicago, IL
Best-selling author, award-winning TV/radio host.

Wow, that is really interesting. We have a lot of brick here in the Midwest as well.

Feb 09, 2011 03:59 AM #38
Rainer
232,298
Bob Zorechak - ABR, GRI, e-PRO
Keller Williams Realty Metropolitan - Morristown, NJ
Sells Homes in Morris/Somerset/Hunterdon Cos., NJ

I've seen these in NJ and southern New England.  Never realized they were used for anything else beyond decoration.  Now I know better.  Thanks.

Feb 09, 2011 04:12 AM #39
Rainmaker
797,356
Barbara Altieri
RealtyQuest, Fairfield and New Haven County CT Real Estate - Shelton, CT
REALTOR-Fairfield County CT Homes/Condos For Sale

I never knew this.  How interesting. $1,000 instead of $8,000?  I'll take the former instead of the latter!

Feb 09, 2011 06:23 AM #40
Rainmaker
646,927
Team Honeycutt
Allen Tate - Concord, NC

Well I just learned something new today!  I always thought they were decorative.

Feb 09, 2011 07:50 AM #41
Ambassador
1,393,364
Erica Ramus
Erica Ramus - Ramus Realty Group - Pottsville, PA - Pottsville, PA
MRE, Schuylkill County PA Real Estate

I have seen that on many old homes in my area and never knew what it was for. I thought it was decorative. Good information.

Feb 09, 2011 07:54 AM #42
Anonymous
Home Repair or Remodel in Arlington TX

Good info.  I didn't know what those were.

www.HouseMendersofTexas.com

Feb 09, 2011 08:14 AM #43
Rainer
318,826
Peg Barcelo
Fluff My House! Home Staging Inc. 250.486.6369 - Summerland, BC
The FlufftasticStager from Summerland, BC

That's really cool! I live in Edmonton, Alberta, where there can be extreme temperature fluctuations up to 45 degrees Celsius! Everything is affected by that, so I will be keeping an eye out, but I'm certain we don't have as much brick up here.

Thanx for the lesson, I love learning new things!

Feb 09, 2011 10:42 AM #44
Rainmaker
513,331
Nick & Trudy Vandekar, 610-203-4543
Long & Foster Real Estate Inc 610-225-7400 - Devon, PA
Tredyffrin Easttown Realtors, Philly Main Line

Interesting, how old world efficiency works even today to hold things together.

Feb 10, 2011 01:42 AM #45
Rainmaker
246,118
Joyce Godwin
12810 Telge,Cypress,TX 77429 -Houston,Cypress,Spring,Tomball - Cypress, TX
RE/MAX Realty Center, Houston Area Relocation Info

Joseph, I haven't noticed those in our area.  I am going to have to take notice and see if they use them here also.  I hope so.  They are pretty.

Feb 21, 2011 11:18 PM #46
Rainer
478,183
Not a real person
San Diego, CA

I would have thought that there were some Dallas Cowboys fans or someone from Texas living there! J

Mar 13, 2011 02:18 PM #47
Anonymous
Julie McCarthy

Tearing off siding on my 1850 brick schoolhouse home. Found 3 of these bolts. Beautiful. My home is happy again. Saegertown PA.

May 26, 2016 10:47 PM #48
Post a Comment
Spam prevention
Show All Comments

What's the reason you're reporting this blog entry?

Are you sure you want to report this blog entry as spam?

Rainer
66,361

Joseph Michalski

PA Home Inspector
Ask me a question
*
*
*
*
Spam prevention

Additional Information