roof ROOF (Throop Memorial Church)

David S. Lawyer

1993-6
Throop church's sloped and flat roofs.

1. SHINGLED ROOFS

2. FLAT ROOFS

3. GUTTERS

4. WHY SHINGLES COME LOOSE

5. ROOF HISTORY

6. Problems 2000-

7. PEOPLE TO WORK ON IT

8. LADDERS

9. Other Buildings with Steep Roofs


1. SHINGLED ROOFS

Slope of sanctuary roof: 14/12; slant height 27 ft. (plus gutter). Area in number of squares (since about 100 ft. long) is 54 squares. The rest of the shingled roof is a little larger than the sanctuary resulting in say 120 squares total. Need to measure for better estimate. Cost to do in 2000 and 2002 (at about $350/square) is $42,000 (excluding cost of replacing rotten wood). The roof of Throop Church was installed in 1986-7 (half completed on Jan. 1 '87 but another source says fully completed on Jan. 1, '87). The roofer was J. L. Shipley Roofing Co. (now out of business). The shingles are "Timberline" made by GAF with a 30 year life and due to wear out in 2017. The color is Burnt Sienna.

Many repairs have been made to the roof, both for the field shingles and the ridge shingles. Some repairs consisted of nailing back loose shingles that were still intact. But other repairs replaced missing or damaged shingles with new ones. One can identify many of the new shingles by their look, since they have a greater contrast between the light and dark spots on them. On the section of roof just W of the minister's office balcony, there is a large section of shingles that were replaced due to a "chain reaction" wind blow-off.

In 1993 and again in 2003 about 80 ridge shingles were replaced by David Lawyer because they had cracked at the top crease due to people walking and/or crawling over them. They are stocked by Cal Western Building Materials at 1095 S. Fair Oaks Ave., 441-2281. We have extra shingles (both ridge and field) stored in the upper tower room. The wood sheathing is 3/4"-7/8" thick and the shingles are 1/8" per ply (part of each shingle is 2-ply = 1/4"). At some points, 3 shingles overlap so the worst case total thickness is 6 x 1/8 + 7/8 = 1 5/8" In addition, the sanctuary roof seems to have a thin mineralized undelayment (visible at the E. edge) which may be an old roof or may just be the misuse of surplus mineralized roofing as underlayment. Roofing nails: For ridge or new shingles:1" or 1 1/4". For holding down loose shingles (visible nailheads):1 1/2" is best (but once used 1 1/4") See the "access" documents regarding how to use ropes to gain access.

Prefolded ridge shingles are available. Use them for next roofing job? Also, metal brackets exist for installing at the top of the ridge for attaching ropes. Would they be strong enough to break a fall? Suppose the wood they are attached to rots? They should be installed only at the rafters so it may be best to wait until new roof is installed.

2. FLAT ROOFS

The N. aisle roof was put on in Dec. '82; S. aisle Mar. '83; Balcony (over kitchen) Aug. '84. The flat roof to the N. of the tower was installed in 1993 (think it's modified bitumen which might last 30 years). Flat roof at top of tower is 16 ft. square => 256 sq. ft. It was reroofed (excluding parapet) in 1995 with modified bitumen (cold apply). The old roof was removed and lowered down in a trash can with a rope. Parapet wall mineralized felt was OK (in 1995) and were connected with the roofing by use of flashing strips cut from modified bitumen using caulk for the joints. Also the joints on the parapet were caulked. The parapet walls contain hollow tile and at least one on the W side was broken (not replaced).

Roof over kitchen (minister's balcony) was supposedly reroofed around 1983. In 1995, a previous coating of something was badly cracked so a coating of Henry's emulsion was applied and painted with Al paint.

3. GUTTERS

The church roof has two sizes of gutters: 6" at the edges of the steep roofs and 7" for the flat roofs. There are also two replacement gutters replaced in the late 1990's: W side office (by stairs) and minister's office balcony.

For the steep roofs, the original gutters (not the two replacements) are attached by a continuous strip of wing (sheet metal which runs under the shingles and is an integral part of the gutter). The straps only attach one side of the gutter to the other side and don't attach the gutter directly to the roof. I'm told (2003) that one can only buy such a gutter with a 1" wing but our wings are much wider than this. As a substitute for the wing attachment, a nail/ferrule method may be used which attaches the gutter to the roof). The nail should be driven into a rafter. Long screws are sometimes substituted for nails. Nail/ferrules were used for the replacement gutters which don't have wings. For the original gutters, replacement straps may be attached to the outer edge of the gutter by drilling a hole and using a 6-32 screw and nut with the upper end of the strap nailed to the roof.

Condition of gutters: Painted inside in 1995: all sacntuary gutters except gutter level with N. aisle roof. Except N. high gutter over chancel not painted but had no rust in 2004. See to_do list.

4. WHY SHINGLES COME LOOSE

Why are the field shingles coming loose? It seems that many field shingles were not properly nailed into place. Not enough nails were used and many were nailed into rotten (or missing) wood. A photograph made during reroofing shows bad and missing wood. The nails used were often too short. A few may have not been nailed at all but the adhesive (which only "glues" a shingle to the adjacent shingle to prevents wind uplift) may have temporarily held them in place.

5. ROOF HISTORY

5.1 1986: Shingled Roofs Installed

In the early 1980's the roof had many leaks and the water leaks did damage. There was a fund raising drive by the "committee of 100" from 1979 to 1987 (8 years) to raise money to reroof the church. The goal was to get 100 people to contribute $100/yr. They raised $36 thousand (excess was spend on carpeting, etc.). Wayne Snively and John Hunnewell were active in it. The shingled roof cost about $20 thousand and the flat roofs about $2 thousand each. About $5000 was spent on gutter repair (but they failed to paint inside the old gutters to protect them).

Only two roofers submitted bids since most roofers refused to bid on it due to it's steepness, etc. Lytle Roofing said the would check for dry rot but were rejected (their bid was the highest). Shipley Roofing's bid was silent re dry rot and as a result the dry rot was not fixed. Shipley did say verbally (per Snively) that there was rot, but said the job was "doable" without repairing the rot. Shipley took out a building permit for the roof on 12-10-1986 but never called for an inspection so the building permit lapsed. Had it been inspected in Jan. 1987 when the new roof was completed it likely wouldn't have passed inspection.

This new roof stopped the leaks but did not hold up well, partly due to shingles coming loose due to rotten wood underneath. A major cause of this rot was the failure to timely repair the roof in the past. Around 1979, when the old roof was leaking, a "Committee of 100" was formed to raise money to repair the roof. It took several years to raise the money, during which time the roof was leaking and the wet wood rotting (dry rot). This damaged the roof boards (sheathing) more, with the result that some shingles come loose easily. This long delay between the observation of leaks and getting them fixed could have been avoided by establishing a reroofing fund and putting some of the budget money in it each year. Then there would have been money to replace the roof. This is also tantamount to depreciating the roof but it wasn't done.

5.2 Problem 1987-2000

During windstorms in 1992 (and prior years), many loose shingles were blown off the roof and as a result the roof leaked rain. At the board meeting of 21 Feb. 1993 the Minister (Norman Naylor) rejected David Lawyer's request to find someone to repair the roof. Abe Ohanian asked why and the minister replied that it was already being looked into. Beth Leehy said that since we can't find anyone to repair the roof we need to install a new roof. I objected but the minutes read "It seems likely, however, that we will have to replace the roof because no one will bid on a repair." This was insanity since a new roof would have cost about $30,000 and was not needed.

The roof was repaired a few months later by a contractor hired by our insurance company. We claimed that the blown-off shingles were a result of wind damaged covered under our insurance policy. The contractor charged them a few thousand dollars for this repair work and used a crane for access. But he failed to repair the ridge singles claiming the damage to them was not due to the wind. This contractor did repair many field shingles. But instead of using roofing nails, box nails with small heads were used. By 2003, many of these had failed: The shingles, helped by wind, pulled up thru the small heads.

In 1995, about 42 shingles had worked loose and were renailed by David Lawyer in Mar. and June. After 1996 other people hired contractors to repair the roof and it seems that one of them failed to use roofing nails.

6. Problems 2000-

After about 1999 repairs were neglected and I sent a series of emails (starting in Mar. 2000) to board members pointing out the problems. Nothing happened (the board sat on the problem). During the first rains of fall 2002, the roof leaked. Then in Dec. 2002 David Lawyer renailed hundreds of loose shingles with the approval of Charles McKinnon, property chair. More were renailed in 2003-4 and all total David Lawyer spent appoximately 60 hours renailing them in 2002-4. This doesn't include time spent shopping for mountain climbing gear to use for roof access.

The field shingles continue to work loose as a rate of about 30 a year. They should be nailed back in place when they first come loose since its much easier to reposition a shingle than to replace it with a new one.

7. PEOPLE TO WORK ON IT

Most roofers will not repair our roof because it's too steep. Explain it to them in detail over the phone so that they don't waste time coming out to look at it. One problem is that OSHA rules are overly strict regarding safety.

Kurt Caldwell, 818-951-1092. Inspected our roof in 1993 and will do repairs on it but insisted on replacing all of the ridge shingle and falsely claimed they were of low quality. Some were cracked only because they were stepped on and not due to low quality. Hire him only as a last resort.

Paul Gavlak (steeplejack). 818-888-8855. Very old and expensive. Will use metal cables with electric motors (boatswains chairs) to work on tower sides. Lives far away.

Paul Clarke (gutter repair) 818-951-1903. Know little about him but looked at our roof and was willing to repair its gutters.

All American Roofing Co., Monrovia 626-303-3737. Said they know how to access it with ropes.

8. LADDERS

Sunset ladder Co., 2526 N. Rosemead Blvd., S. El Monte. Bought rung locks from them in 1993.

Roofmaster, 750 Monterey Pass Rd., 213-161-5122. Sells ladder hooks ($15) for catching on ridge. Sunset ladder only has hooks with sharp points which would damage shingles. But would need 30 ft. one-piece ladder.

9. Other Buildings with Steep Roofs

(Ask who repairs theirs.)

1. Westminster Presbyterian Church on N. Lake Ave.
2. San Marino: Virginia Rd. 975, 1221.  Oak Grove 945, 1251.