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                             R. Putnam Construction Services, LLC

"Helping Build Your Future"

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Now Serving Oregon!

Posted on April 6, 2015 at 5:15 PM Comments comments (2)

I am very happy to say that R. Putnam Construction Services LLC is now a Washington and Oregon company. I look forward to serving our Oregon customers with the same commitment and quality that has guided our work in Washington.

Foundation Venting and Crawlspace Moisture

Posted on June 11, 2014 at 1:15 AM Comments comments (0)

There are a lot of ways to grow value or equity in a home. One way is to add improvements or details that are both useful and aesthetically appealing. Another way is to maintain the home is a useful and healthy condition. In the western side of Washington State, for example, it tends to rain a little more, so having an exterior covered porch or awning can increase the number of days a patio can be useful. It can also prevent that mysterious yellow ball from upsetting your perfectly white skin tone.

 

Insulation is not as important here. The temperature is typically moderate unlike where my daughter lives in Pennsylvania where wind chill temperatures will commonly reach below 0 degrees in the winter and summers can decrease the need for indoor saunas. Building code still requires good insulation in new homes, but often, older homes have less insulation. It is not uncommon for home built before 1975 to have six inches or less of insulation in the floors. Often older buildings and commercial establishments have no insulation in the floors. Being industrious, home owners might be tempted to take advantage of a wonderful product called foundation vent blocks to control the winter frigid air from making your floors and therefore your poor feet too cold. Unfortunately, these wonderful little $1.50 items come with a risk: while making consumers feel they have solved the problem of cold drafts and frozen pipes, they may be inviting more expensive problems.

 

Over the years, I have known many people who tried to save money, prevent freezing pipes, and keep floors warmer by blocking off the foundation vents around their house. Although there is disagreement to the universal value of venting in foundations , it is typically agreed that moisture trapped in a crawlspace is not a good thing. Be careful not to assume that because blocking a vent is widely touted as a good thing in another part of the country, that you do not blindly follow the practice.


 

Trapped moisture can cost you thousands of dollars in repairs. In the worse case scenarios, it can make a house uninhabitable due to mold and mildew growth and damage.

 

I once was called to inspect a business where the tenet had experienced a spongy floor. Crawling under the floor made my skin crawl. Although, I do not have the original pictures any longer, the sight was very similar to shown in Rachel Hulan's blog here.


The floor along a 30' wall was totally covered with fungal growth. Over half of the business was required to shut down and the removal/repair costs were extensive.

 In another case, a corner of a house had started to settle but there was no indication of foundation failure/settling. It turned out that the foundation vents for that corner of the house had been blocked several years and the rim joists and 10 floor joists had dry-rotted. The repair costs were about $4,400. A lot of insulation and plastic sheeting can be bought for $4,000.

 

General facts about foundation venting.

• Foundation venting requirements vary in different parts of the country. Consult local codes for guidance. Some areas have greater degrees of ground moisture, temperature fluctuations and gas exposure (radon or methane gas for example).

o In general, regions that have lower outside humidity levels are better to keep vents unblocked. Regions with higher humidity outside may benefit from restricting that moist air from the crawlspace. However, if moisture is still trapped from other causes, negative effects of moisture can still occur.

o The National Association of Certified Home Inspectors indicate that "One square foot of net free vent area is recommended for every 1500 square feet of floor area covered by a polyethylene vapor retarder. Ratio is 1:150 if vapor retarder is not used. (NACHI blog)

• In areas where the crawlspace in artificially conditioned (i.e. humidity and temperature are controlled) a crawlspace does not require ventilation.

• "Venting will reduce crawl space moisture levels. Venting will only help reduce crawl space moisture levels when the outside air is dryer than crawl space air, or when enough hot outside air enters and warms the crawl space."

o Consequently, it is important to confirm that other steps are taken to ensure that moisture is not trapped under a home (see Other Considerations).

• A reasonable amount of moisture in crawlspace air is a good thing. In general, humidity recommendations range from 30-50% in a building.

 

 Other Considerations:

• Ensure that downspouts are directed away from foundations so that water will not tend to accumulate along a foundation or under a house.

• Installing a 6mil polyethylene sheeting (sometimes called: visqueen or simply plastic) as a vapor barrier (or retarder) over the bare soil under a house will reduce the moisture evaporated from the ground in the crawl air and lower the required venting needed for the crawlspace. Note: some states require thicker sheeting.


• Land around a home should be sloped away from a house to allow proper runoff away from the home.

• Hard-wood floors, furniture and other building materials desire reasonable moisture content levels to prevent cracking, cupping, shrinking and expansion. Building materials constantly adjust moisture content based on the surrounding environment.

o Consider installing a humidistat in homes that fall outside these variables and humidifier/dehumidifier to help regulate moisture content levels.

 

Further Reading:

The Effect of moisture on wood

Crawlspaces Require Ventilation

Conditions for mold growth

Mold Types Found In Homes

 

Disclaimer

Posted on June 1, 2014 at 4:35 AM Comments comments (0)

Thank you for visiting our site. I hope that you will enjoy it, learn some bit of information that helps with your projects, and most of all help you add equity and safety into your projects.

 

The information posted is constantly being checked for content, clarity, and correctness. That being said, the tips, practices, and codes may not be perfect for your particular project. When considering a project, it is best that you consult with people skilled in providing critical information in the building trades and services. This may require you to retain a good contractor, engineer, or architect to ensure your project is designed and built using all applicable laws, code requirements, and practical procedures.

 

Although this site is established, in part, to teach, we are not responsible for its interpretation or application of guidance herein to any specific project. Codes, materials, and requirements are always changing. Check with your local building department for specific requirements for your project.

 

Building Codes: Just more regulation or common sense?

Posted on June 1, 2014 at 3:10 AM Comments comments (0)

Not all codes make sense.


If you have been involved with any building projects, no doubt you have had to deal with a local building department. The process is not overly challenging but it can be a little daunting trying to understand building code requirements and then applying the required codes to your building project. Drawings, required materials, load, stress, tension, uplift . . . the frustration has already begun and all you wanted to do was build a small addition. On top of that, some of the requirements don't seem to make a lot of sense. For example, in Washington State, if you are adding an addition the 2x6 exterior walls are required to have insulation with a R-21 insulation value "at heated areas (R-15 where glass is less than 12% of floor area)." Insulation is good, of course, it saves energy, monthly heating and cooling expenses and makes a room generally more comfortable. But what if your home was built in 1969? Back then the insulation codes were vastly different. It was not uncommon to have R-11 insulation, if there was any at all, and often, in my experience, it was installed incorrectly. Consequently, 90% of your home may be have a R value of less than 11 but the code requires any new exterior walls be installed at current code. Makes sense, right?

 

Most codes are adopted to protect the occupants.


Nevertheless, most of the codes which have been adopted are there for the protection of the occupants and to standardize good quality construction. Take this example for instance:

 

A rental repair project included an awning roof built over an existing patio. The roof structure was built some time ago without a permit and for years seemed to serve its purpose of decreasing light through the back patio door as well as a pleasant covered area for sitting. I was told that the children used to climb out of the upstairs windows and onto the roof at night: a story that still gives me chills. The original plan was to clean it up and work on some leaking issues along the wall it was connected to. After closer inspection a number of code and basic design flaws were found in the structure.

 

Ledger Board improperly fastened to wall


Removing the soffit exposed the ledger and the five 1/4" bolts that were attaching it to the wall. The fact that the ledger board was fastened over the vinyl siding and there should have been approximately 14 fasteners mounting the ledger is bad enough, but even the existing fasteners were not installed well. The home was built with a silent floor system which does not have a standard solid rim joist. The five fasteners were attached to 1/2" OSB sheathing (OSB Rim Board) only. That is pretty much like anchoring into sand. Code, depending on the overall load, requires that fasteners be typically fastened into solid wood (or 1" EWP band board) with bolts or SDS Screws staggered every 10-16" on center (check local codes for specifications). Here is a good guide for more understanding.


Rafters span to great of a distance


Structural members, based on their properties, have limitations on how far they can span. With this awning roof the 2x6 rafters, placed at a 2/12 pitch and 24" on center (o.c.) were constructed with a 12' span. 2x6 rafters, according to the American Wood Council can span about 8 feet at 24" o.c. Twelve foot rafter spans require 16" spacing or 2x8's (or more, depending on other issues such as uplift, snow loads, or roofing materials used).


Improper metal hanger attachment


Simpson Strong Tie connectors are used for fastening the rafters to the ledger board. Depending on engineering requirements, a Simpson LRU or LSU Rafter Hanger. These are fastened with 1-1/2" Teco nails and 10d common nails. You will notice that the nailing in the picture is not complete, had bent nails and the nails were incorrect. People actually sat under this roof.

 


Improper roofing installation


As I mentioned in another post, asphalt shingle systems are made to work for 2/12 and greater pitched roofs. Roofs less than 4/12 require special steps to prevent moisture penetration. I prefer a minimum of 3/12 pitch roofs for asphalt shingles because I have had to replace too many structures where the 2/12 pitch did not adequately remove the moisture allowing water to seep back beyond the shingle upper edge and damaging the underlayment.

Materials need to be selected based on the use, location, and resulting requirements/needs. Simply because others have installed a particular way, does not make it a good idea. On this roof, the material had been leaking through for some time even though the asphalt shingles were applied on a 2/12 pitch roof. The owner was very surprised because no leaks were spotted under the roof except for at the ledger board. Why was the leaking not noticed? Because the water was dripping through the sheeting and getting caught in the vinyl soffit material. There it either ran to the sides or evaporated over time. The picture shows the stains from stagnant evaporated water.

 

Improper protection of OSB sheathing


OSB sheathing, or Oriented Strand Board, can be a very good product. It is a result of the desire/need to conserve resources and use forest materials more efficiently. By taking wood pieces and compressing them together with exterior adhesives, the panels can be made and cut into 4'x8' panels and used instead of plywood (which has become very expensive). OSB has a flaw though: it does not hold up well to moisture — especially over a long period. Sealers have been added to panels to control some deterioration but the edges must be protected from moisture or they will expand and delaminate. It is not an uncommon problem. To control this problem, roofing projects must be pre-inspected before new roofing is installed to ensure sheathing panels do not need to be replaced before covering.

This roof did not use protective metal edging or other wood cover and did not extend the roofing beyond the OSB edges to protect it from water. The same occurred at the gutter where no flashing was installed (often this is not required because many gutter profiles provide a flashing edge).

 


The moral of the story is that building codes are typically very practical, and even though the permitting process can be intimidating, costly, and occasionally frustrating, the codes — and the professionals who inspect for them — are your friends. This roof was removed and not reinstalled. Thank goodness roof did not fall with people on or under it. The result would have been much more costly than the minor permitting, and material costs to do the job right.


 

Roof Slopes and Choosing Roof Materials

Posted on May 31, 2014 at 2:50 PM Comments comments (0)

The slope of a roof is partially for design and structural purposes but also to meet the requirements of a particular product so that it may be installed correctly. Roof slopes less than 2/12 (or 3" of rise for every 12" of run) require solid forms or roofing (like modified bitumen, metal sheeting, or rubber membrane) in order to properly shed the rainwater or melting snow away from the framing structure. Roofs greater than 2/12 can use more common roofing like 3-tab or architectural asphalt roofing. My personal preference is that a roof has at least a 3/12 pitch roof before using asphalt shingles. I have removed enough damaged roofs to know that in our wetter climate, lower pitch roofs have difficulty adequately shedding the moisture. According to NACHI (National Association of Home Inspectors)rolled roofing is a recommended product for slopes from 1/12 through 4/12 and asphalt shingles are suitable for low slopes (from 2/12 to 4/12) with added measures to prevent water damage.



Blog Goals

Posted on May 29, 2014 at 9:05 PM Comments comments (0)

Welcome to our blog. In coming weeks we will be providing many helpful tips and guidance on how to build your home equity. Then we will work with you to help you accomplish your dreams.


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