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1CRENSHAW UMC ROOF REPORT

January 20, 2015

Dominion Seven Architects was commissioned to evaluate the condition of the existing roof systems at the church, note areas of concern, note the potential remediation and develop cost estimates for the remediation. Our firm was on site on November 4, 2014 to evaluate the roof.

Existing ConditionsThe church was built in stages with the original portion dating back to the early 1900’s. The education wing was constructed 25 years later and the most recent addition dates to the early 2000’s. The roofing systems are a combination of slate and asphalt shingles, metal and EPDM rubber membrane.

The church has completed a variety of roofing projects over the last 10 years, but these projects were not extensive enough to provide long term watertight solutions.

The following is a description of the existing conditions for each area of the church. We have divided the church into 7 different roof sections.

1. Sunday School Wing Roof:

The Sunday School wing roof is a “T” shaped element that is difficult (and dangerous) to access. An aluminum extension ladder must be used to gain access. Due to the difficulty of actually getting on the roof, maintenance staff rarely monitors the condition of the roof. The ladder that the church uses only extends up to a cornice, which is approximately 4.5 feet below the top of the parapet wall. One must stand on the cornice and pull themselves over the wall. This is a significant liability issue for the church. The potential for falling off of the cornice or ladder is high.

The 4,990 square foot roof is sloped from south to north at a pitch of 1/2 inch to a foot. It appears that the original roof was a built up roof (tar and gravel) that is installed over a wood deck. About 10 years ago an Ethylene Propylene Diene Monomer (EPDM) membrane was installed over the original roof. The new membrane is probably installed over a “recovery board” which is probably a thin wood fiber board. The recovery board is screwed to the roof deck and the membrane is glued to the recovery board. The membrane appears to be in 12 foot wide sheets. The roof manufacturer is Mulehide and the roof has a 10 year warranty which is expiring.

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This type of roof system is very common and is a very good solution. EPDM is often referred to as a “rubber membrane”. It is very flexible which allows it to move and stretch with the changing temperatures. It is black in color. Note that on a 90 degree summer day, the air above this roof can reach upwards of 150 degrees.

If installed and maintained correctly this type of roof can last upwards of 30 years.

A couple of years ago the building was experiencing leaking along the north wall. The lower section of the roof was replaced at that time.

The roof membrane also extends up the parapet wall to the cast concrete coping stone where it is connected to the wall with a metal termination bar. The parapet wall on the north side is about 5 feet tall and about 2.5 feet tall on the south side. Portions of the membrane on the parapet wall were replaced with the remediation project in 2012. Essentially this type of design creates a bath tub type design and is typical for roofing installations.

This rubber roof was installed by a roofing contractor whose expertise is mainly the installation of asphalt shingles. The Mulehide certified contractors are typically a second tier contractor as opposed to Firestone’s or Carlisle’s roofing contractors. This means that the Owner is not getting the best of the best when it comes to installers. It is important to note that the roofing materials (membrane, flashings, adhesives, etc.) rarely fail. Roof failures are typically because of poor installations. The workmanship is the key to a quality roof, regardless of the materials used.

The roof membrane appears to be in good condition. Our concern would be how it was installed. The original built up roof should have been removed down to the wood roof deck. New rigid insulation should be installed on the deck and then the rubber membrane adhered to the insulation. Portions of the original roof have collapsed from water infiltration which has caused low spots for water to collect as noted in the picture below.

3Crenshaw UMC Roof ReportJanuary 20, 2015

Additionally due to several reasons, which will be discussed later, water ponds along the north wall. Note the two pictures below. In the first picture the discolored area shows the limits of the ponding water. In the second picture, ponded water is still visible on the roof. Note that this fall has been unusually dry (prior to our visit the last significant rainfall was on October 15), so this water has been on the roof for weeks.

Water from the roof exits the roof by means of four roof scuppers, which are holes through the parapet wall. Water flows through the scuppers to a leader box and then into a downspout. At some point the church was concerned about the ponding water and decided

4to increase the size of the downspouts with the hopes of getting the water off of the roof faster. This solution was flawed for a number of reasons:

Reason #1: When the rubber membrane was installed the contractor did not install “crickets” along the wall. Crickets are angular shaped, sloping structures that are typically made up of tapered insulation and force water to flow around impediments or towards roof drains or scuppers. Looking at the right hand picture above, a cricket would have resolved the ponding water in the corner by directing the water towards the scupper (not seen in the picture).

Reason #2: The size of the existing scuppers is very small. The largest is 4 inches wide by 2.5 inches tall. The smallest is 4 inches wide by 1.5 inches tall. The total area of the four scuppers is about 32 square inches. The scuppers are undersized by 20% to 50% depending on the location and based on the expected rainfall intensity of this area. Scuppers have to be properly detailed so that water does not leak into the wall cavity. Copper flashing is typically wrapped around the four surfaces of the wall and then the roof membrane is extended over the copper flashing. For this reason, scuppers are significantly larger than what is present on the church so that this level of waterproofing can be executed.

Crenshaw UMC Roof ReportJanuary 20, 2015

Reason #3: Note the picture below. One of the scuppers is blocked by a plumbing waste vent, which greatly reduces the flow of water to the scupper.

Reason #4: Lastly, the bottom of the scuppers are higher in elevation than the roof plane. See the picture below. There is nowhere for the water to go and thus it waits to be evaporated.

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The quality of the workmanship on the rubber membrane is generally poor on the parapet walls. Note the two pictures below. In the first picture, the membrane is peeling off of the parapet wall. In the second picture, note the craftsmanship of the membrane installation in the corner of the roof.

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Another aspect of the lack of attention by the roofing contractor, were the numbers of roofing nails and screws that we picked up off of the roof. The membrane is generally very tough to damage, but is very susceptible to anything sharp. Also the contractor left materials on the roof as noted by the container of membrane cleaner. This product is highly flammable. See the two pictures below.


The existing cast concrete coping stones are extremely weathered and are probably the biggest source of water infiltration into the building. These stones protect the exterior walls which are solid masonry. Attempts have been made over the years to paint the stones. Note in the picture below the remnants of the black paint. Also the joints have been filled with a waterproof coating. These are good temporary fixes, but not a long term solution.

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Along the parapet walls are four flues. We are only aware of one that is active. An open flue is also another opportunity for water to enter the building. The three that are not active should be covered with a metal cap. The one that is active should have the cast concrete covered with a waterproof material. See the picture below.

This portion of the church was designed with a wood cornice that wraps around the entire façade. The top of the cornice was covered with copper and flashed back to the brick veneer. Wood is a maintenance challenge that requires regular painting and thus at some point in time the wood was covered with white break metal. We noticed a couple of issues with this architectural feature.


Note in the photograph on the left that there has been some movement of the copper flashing away from the wall. This is allowing moisture to enter into the wood cornice. The flashing appears to be nailed into the veneer versus being installed into a reglet in the mortar joint as would typically be done. Note in the picture on the right another issue with the cornice is that a section of the white break metal has become disconnected from the cornice.

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2. High Roofs of the 2002 Addition:

There are two high roofs that are adjacent to the Sunday School Wing that cover the elevator shaft and fire stair that were constructed in 2002 totaling approximately 230 square feet. These roof systems are comprised of EPDM membrane and 2 inches of rigid insulation over metal roof decking. The roof slope is 1/4 inch per foot, which is the minimum slope for a membrane roof by code. Both of the roofs are drained by a 4 inch by 4 inch scupper. There is a short parapet wall around the roofs that are capped by a cast concrete coping. The parapet walls align with the adjacent Sunday School walls. Both of the roof planes are higher than the roof plane of the Sunday School wing.

Some water ponds at the scupper, but this is not surprising based on the shallow slope of the roof.

The installation of this membrane is superior as compared to the one on the Sunday School wing, but it is also installed over a surface that is newer and more consistent in configuration. The warranty on this roof is unknown, but should have around a decade of life remaining.


The installation of the cast concrete coping is very poor. Note the gap that is being infilled by a piece of treated wood that has been hammered into the gap in the picture below. The length of the coping was incorrectly measured or manufactured, thus creating the gap. The Contractor appears to be aware of the problem and installed a small piece of coping on the front side to hide the error from the average person when viewing this condition from the ground.

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The masonry contractor would have been responsible for setting the coping stones. They did a very poor job. See the two pictures below. In the first picture, note the differences in height of the adjacent coping stones. In the second picture note the center section of the coping stone that is higher than the adjacent coping stones.


Another issue with the coping stones is the regular maintenance required to caulk the joints. These joints need to be re-caulked. These joints are a typical water infiltration location. See the picture below.

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Similar to the Sunday School wing, a cornice constructed of wood framing and break metal wraps around the exterior. The size and configuration of the cornice is a little different than the adjacent one, but it seems to be in satisfactory condition. We did notice one area of concern where the downspout from the scupper enters the cornice. This area was never properly sealed and thus allows water to enter the cornice below. This problem is repeated on the underside of the cornice as well.

Also note in the left hand picture that the gap between the flashing and wall needs to be caulked behind the downspout.


3. Low Roofs of the 2002 Addition:

On the east side of the building between the Sunday School wing and Sanctuary is a section of roof that has both a rubber membrane roof and an asphalt shingle roof. The membrane roof is a 553 square foot area shaped like a square and slopes at 1/4 inch per foot. The

11membrane is installed over 2 inch thick insulation which is adhered to wood sheathing. The membrane is turned up the side of the adjacent brick walls approximately 8 inches and sealed with a termination bar. There is an exhaust fan that penetrates the roof, which probably serves the elevator equipment room. The membrane appears to be in good condition.

The hipped shingled roof is approximately 1,594 square feet in area. It has a 5:12 pitch and is drained by gutters and downspouts around the perimeter. There are two concerns with the shingled roof. The first concern is the 3 downspouts from the higher roofs that empty onto the shingled roof, which over time will erode the granular surface of the shingles. See the pictures below.


There appears to be a leak adjacent to the sanctuary in a storage closet. The stepped wall flashing in this area appears to be sound. We believe the problem is at the pitch pocket which is the waterproof condition around an electrical conduit. See the picture below.

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Another concern is the ventilation of the attic space in the 2002 addition. The shingle roof is currently vented through the soffit, which is good; however ventilation through the high part of the roof is required by the building code. The original drawings call for two ridge vents in the shingle roof. Only one vent was installed. The drawings also call for four gravity vents in the membrane roof. None were installed. A lack of ventilation will prematurely deteriorate a roof system. See the picture below of the ridge vent.


4. Western Porch Roof :

The western porch has a flat roof and is located between the Sunday School wing and the Sanctuary. The roof is approximately 218 square feet and the roof system is a membrane roof over an unknown substrate. Our assumption is that this roof was also installed over a

13built up roof which was installed over a wood deck. The roof appears to have a 1:12 pitch from east to west, but the roof then flattens to dead level along the western side. It is along this side that water ponds. See the picture on the left. Towards the bottom of the picture is a 6 inch by 6 inch scupper. See the picture on the right. Due to the adjacent trees this section of roof collects a significant amount of leaves which clogs the scupper.

Also note the horizontal brick joints in the picture on the right. They have deteriorated over time and the mortar eroded. The bricks need to be covered with the rubber membrane or repointed to prevent water intrusion.


5. Curved Low Roof at the Sanctuary:

Between the Sunday School wing, West Porch and the 2002 addition there is a low curved roof that wraps around the rear of the sanctuary that is approximately 1,000 square feet. This roof is a rubber membrane roof that slopes at a 1:12 pitch away from the Sanctuary. A cricket is located at the edge of the Sunday School wing that pushes the water towards the west and east. Gutters collect the water from this roof. It appears that the original roof was

14metal, which, based on the sound while walking on the roof is still present. The membrane appears to be in good condition. See the pictures below for images of the east and west sides of the roof.

There are two large Heating/Ventilation/Air Conditioning (HVAC) units mounted on the roof that serve the Sanctuary. The units have some age based on the exterior condition of the unit. Our belief is that these units are 25 to 30 years old. The units are located on a raised metal frame that is supported by 6 metal legs. Each leg has a pitch pocket that provides a waterproof condition. There should be rubber walk pads from the roof access point to the units and around the units.


The single biggest issue with this roof area is the condition of the gutters, which need to be replaced. The current ones have pulled away from the roof. See the pictures below which are on the east side. Note in the picture on the right side that the end of the gutter is actually being supported by a concrete block.

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The pictures below illustrate the nails and hangers pulling away from the framing.


6. Main Sanctuary Roof:

The cruciform shaped, 3,184 square foot main sanctuary roof is comprised of three gable roofs and a curved apse end roof. The roof is clad with slate shingles. Some of the shingles

16have been replaced over the years. See the pictures below. Note the shingles of different colors, which helps to understand the areas that have been reworked.

Slate roofs tend to be very fragile and are inclined to break or crack over time, particularly if they sustain foot traffic. Note the two pictures below. In the picture on the left, the red circles note areas of missing slate or broken slate. The picture on the right notes a shingle that has been stepped on and broken.


The ridges and valleys of the roof are of copper, which is the ideal material for this application. See the pictures below. Note how the ridge is bowed in left side picture. There is also some variation across the plane of the roof. Both of these may be structural issues that need to be evaluated. Note all of the broken slate at the bottom of the valley in the picture on the right side.

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There is a masonry parapet wall that acts as a means of terminating the slate shingle roof. The parapet wall is capped with sheet metal that has been painted red. This coping material is maintenance intensive and is currently in need of replacing.

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Crenshaw UMC Roof ReportJanuary 20, 2015Page 17

The transition between the slate shingles and the parapet has been compromised with age and reworking of this condition over the years as seen in the picture below. There are a series of problems with this detail.

The step flashing which is circled in red has begun to rust, which means it is sheet metal and not copper or aluminum, which are preferred materials.

Note that any openings like the one circled in blue are not only an opportunity for water to enter the building, but also vermin (primarily insects).

Note the bent parapet counterflashing circled in green. Note the amount of caulking along the vertical edge of the parapet wall. These types

of repairs are very temporary. Also note that the shingles do not completely cover the edge of the roof on the left

side. The white mesh material is roofing felt. See the next page for a further discussion of

the roofing felt.

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The photograph on the previous page leads to another significant concern. See the photograph below, which is taken from the left of the picture above and looking at the side of this condition.

The ends of the wood deck boards are exposed to the weather. There should be metal flashing that turns down the side of this condition and covering the wood.

Note the piece of plywood that has been added on top of the wood deck boards. That tells us that the edge roof has sunk (water damage?) at the tails of the rafters. The purpose of the plywood is to bring the edge of the roof back into plane.

Note also the conduit which is probably a condensate line for the interior HVAC system.

Also note the hole that opens the attic up to the exterior.

When we see conditions like this it tells us that the roofing contractor does not know how to properly execute the details to keep it watertight. It is our understanding that the Contractor who completed work on the Sunday School wing also reworked the slate shingles. It is very apparent that the majority of the issues on the building are workmanship related and not failure of the materials themselves.

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There are several other conditions where the wood roof deck is exposed to weather. See the pictures below, which are taken at the gutters. Once again there should be metal eave flashing that covers the wood that can be seen. We have highlighted the exposed wood with red circles.

The downspouts shown below are damaged and rusted, and need to be replaced. The material is sheet metal which has a short life span as opposed to copper or aluminum. Note also in the picture above on the right side that the gutter nails have started to pull out. Note the picture on the right where the downspout empties onto a splash pad, which is the correct method for protecting a roof.

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During our inspection of the roof, we noticed an interesting condition. The roof rafter tails extend past the exterior walls and are exposed. We assume that this was a decorative feature. When the Sunday School wing was constructed it obstructed the view of this detail from the ground. See the picture below on the left for the exposed rafter and note the hole that opens up directly into the attic.

Since the rafter tails had to be painted, they became a maintenance issue. At some point in time, an aluminum soffit was installed to enclose the exposed rafters. In numerous locations the soffit is failing and has collapsed. The picture above on the right shows the collapsed soffit.Another example of a collapsed soffit is shown in the photograph on Page 12, top right hand side. This condition also occurs on the curved section of roof at the rear of the Sanctuary.

We also noted yellow jackets on this section of the roof, which we assume have made a nest inside the attic area of the Sanctuary.

7. Front Towers:

Across the front of the building are two towers of differing heights and differing designs. The tower on the left (when viewed from Church Street) is the taller structure. It serves as one of the two original entrances to the church and as the bell tower. The left tower has two roof systems that occur at different levels. The first is at an intermediate level that is enclosed by 12 arched masonry openings. This roof is accessed from the interior by means of a roof hatch. We did not get on the roof, but it appears to be constructed of metal that has been painted white. We are not aware of any leaks in this area. The second roof serves as a cap on the tower and is a steep copper roof. There are four brick pilasters that extend past the bottom of this roof that are also capped with copper. This roof also appears to be sound. See the picture on the next page for a close up view of the lower roof.

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The right tower is wider and half of the height of the left tower. Like the left tower it has two roofs. The lower roof is also painted metal and is enclosed with eight masonry arches. The rear section of the wall around this roof is solid. The exterior surface is painted sheet metal. We did notice some rusting of this roof. The upper roof is located behind a crenellated masonry wall. We assume that the roof is also metal. It has a scupper with a downspout that empties onto the slate shingle roof below. Both of these roofs need to be further evaluated and repainted as necessary. The painted metal façade should also be repainted.

At the base of the towers where they intersect the slate shingle roof of the sanctuary there is a copper valley that moves water from the front of the church to the side. A scupper, leader box and downspout take the water from the gutter. Unlike the scuppers on the Sunday School wing, these are adequate in size (9 inch by 5 inch). See the picture of the scupper on the next page. Note the copper valley, the copper counterflashing on the left side and the rusted sheet metal parapet coping.

23Crenshaw UMC Roof ReportJanuary 20, 2015Page 22

The valley has a very low slope from the front of the building to the rear falling only about 1/2 inch in 12 feet. This is a near level condition that should be corrected to allow for adequate water flow around the tower. The section of the valley across the rear slopes at approximately 4 inches in 12 feet (or 1/4 per foot), which is a recommended minimum slope. See the pictures below for additional views of this valley. The left picture shows the entire valley from the viewpoint of the ridge of the sanctuary roof. The right picture is the view towards the front of the church. Note the amount of broken shingles.

Crenshaw UMC Roof Report

24January 20, 2015Page 23

Lastly after we had finished our inspection of all of the roofs we had collected additional debris from the roofs. We left the pieces of slate, but disposed of the rest of the material. The picture below is a continuation of the same group of debris that is shown in the picture on Page 4.

RecommendationsThe following are recommendations for each area of the church and the associated cost for construction.

1. Sunday School Wing:

Roof System : We feel that the best long term solution is to remove the existing roofs (rubber membrane roof and built up roof) down to the wood deck and replace it with new rigid insulation (polyisocyanurate) of at least 4 inches (R-24 insulation value) and a new fully adhered EPDM membrane. The wood deck would be inspected for water damage and replaced only as necessary. The membrane would be turned up and across the top of the parapet wall. Then a new metal coping would be installed over the top of the wall. Inactive flues would also be capped by the metal coping. As part of this work the scuppers would be enlarged and the plumbing vent relocated.

Cost: $90,350

Roof Hatch : A new roof hatch should be provided so that the roof can be accessed safely and on a regular basis by the maintenance staff. The hatch should be located on the high side (south) of the roof. We would recommend a Bilco Type S model.

Cost: $2,000

Wood Cornice : Repairs to the wood cornice would include securing the copper flashing on the top of the cornice back to the brick veneer and reconnecting any loose break metal. The ideal time to complete this work is when other roof work is occurring.

Cost: $29,750

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2. High Roofs of the 2002 Addition:

We would recommend replacing the EPDM roof and insulation. Other additional repairs that are necessary would be to wrap the existing would cornice with new metal, install metal coping over the coping stones and to reline the existing scuppers. New leader boxes and downspouts would also be provided as part of this work.

Cost: $15,045

3. Low Roofs of the 2002 Addition:

For this portion of the roof, the recommended changes are minimal in nature. The roofing in general is in good shape, however, proper attic ventilation is currently not being provided. Improper attic ventilation can lead to roof failure over time and also can void any roof material warranty provided by the roof material manufacturer. We would recommend removing the existing ridge vent and installing shingles at the ridge. A powered roof ventilator should be added to ensure proper attic ventilation.

Cost: $1,450

4. Western Porch Roof :

We would recommend replacing the EPDM and insulation in this area. Relining of the scupper and installation of a new leader box and downspout would also be provided. The parapets would be covered with new metal coping. To ensure easier roof access for maintenance purposes, a new painted metal roof ladder would be installed.

Cost: $6,165

5. Curved Low Roof at the Sanctuary:

We would recommend replacing the EPDM and insulation in this area. New gutters and downspouts would also be provided. New pitch pockets at each support leg of the structure supporting the rooftop mechanical units would be provided as well. The supporting structure for the rooftop mechanical units would also be given a fresh coat of paint. To ensure easier roof access for maintenance purposes, a new painted metal roof ladder would be installed. The existing vinyl soffit material would be removed and replaced with new ventilated metal soffit.

Cost: $20,345


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6. Main Sanctuary Roof:

Due to the nature of the work that we would recommend in this area of the roof, we have provided multiple options as explained below:

Option #1: Repair the existing slate as required. Cost: $90,500

Option #2: Remove all existing slate and install new slate. Cost: $158,375

Option #3: Remove all existing slate and install new synthetic slate. Cost: $135,750

Other roof work that would be recommended to be completed regardless of which of the above options is taken would be to provide new metal coping at the parapets. Relining of the scuppers and new leader boxes and downspouts would be provided as well. To provide safer roof access, 2 new roof hatches with ladders and safety posts would also be provided.

Cost: $9,200

7. Front Towers:

The existing roofs on the towers appear to be in good shape at this time and therefore no work is recommended for these areas.

We would also recommend that a structural engineer be employed to evaluate the condition of the ridge beams and roof decking on the slate shingle section of the roof. The approximate cost of this effort is between $1,800 to $2,000.

Sincerely,

______________________________Blair Smith, RA, LEED AP

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