The new wood deck repairs throughout your community have been coming along nicely, and the repairs make the decks themselves look almost brand new. However, a few weeks after repairs are finished, you make a startling discovery: the new wood members are beginning to crack! Were the repairs completed improperly? Was subpar wood used? Have you wasted time and money on repairs that will need to be redone? Fortunately, most of the cracks you are seeing in the new wood members are a natural part of the wood’s acclimation process. As “green” (i.e. wet) wood naturally dries over time, it shrinks, causing cracks to form along portions of the wood. A “check” is a crack that occur parallel to the grain of the wood, while a “shake” is a separation of the growth rings within the lumber. While these cracks may appear unsightly, they usually do not affect the structural properties of the wood, unless the check or shake runs through the entire depth of the wood member. Properly acclimating the wood pieces to environmental conditions and specifying higher grade lumber can help minimize this cracking, but green lumber will always display some external cracks as it dries. Also, additional cracks may occur as the wood is exposed to varying environmental conditions throughout the seasons. If you still have concerns about cracks in your wood structures, ETC can help evaluate these cracks and put your mind at ease
Metal guardrails can provide stylish, long-term fall protection for balconies, walkways, garages, and many other elevated structures. While metal guardrails can last almost twice as long as wood guardrails, periodic maintenance is still required to ensure they remain serviceable and do not pose any life-safety hazards due to deterioration of the aging railing components. A few steps taken every few years can allow these vital building components to last well into the future of the building:
- Understand your railings. Are they aluminum or steel? Do they have a protective coating such as a powder coating? Are they surface mounted or embedded into a concrete slab? The answer to these questions and many more are crucial to determining exactly which approach is best for maintaining your railings!
- Routine cleaning of the guardrails will help remove built-up organic growth and other stains that could contribute to deterioration of the railing finishes.
- Make sure water has a way to get out of the railings. Many times, these railing systems are comprised of numerous hollow tubes which can trap water that enters the railings through cracks or holes or from condensation build up. The placement of weep holes throughout the assembly and especially at the post bases can help evacuate water from the railing interior, reducing the potential for corrosion of the metal.
- Restore protective coatings. Peeled/missing coating will expose the underlying metal member to elements, exacerbating corrosion at these areas. Recoating railings will ensure this protective cover between the metal and the environment will remain effective.
- Clean corrosion as soon as possible! It is imperative to clean corrosion from steel members before it progresses to section loss. If holes start appearing in the guardrails due to corrosion, more intensive repairs measure will be required, including replacement of the member.
If you are looking for a professional evaluation of your building’s railings, ETC can provide the evaluation services you need.
As construction techniques continue to grow and evolve, choosing the right material for your job may seem a little overwhelming. This especially rings true with timber construction. Gone are the days when you just needed to specify the size and tree species. Here’s a guide to help you choose the timber that is best suited for your job.
Sawn Wood‐ Traditional sawn wood is still the commonly used type of lumber. Almost all structural sawn wood beams originate from softwood tree species, such as Pine or Douglas Fir. Structural sawn lumber is further classified through stress‐gradings, which establish standard working values for properties that can be used to determine the load‐bearing capacity of these members. Typical lumber grades can be seen on the adjacent table. Traditional sawn lumber can be used for almost all structural member, such as joists, beams, posts, etc.
Laminated Veneer Lumber (LVL)‐ Laminated veneer lumber belongs to a family of engineered wood products called structural composite lumber (SCL). Structural composite lumber members are comprised of blocks of lumber materials know as “billets”, which are veneers, strands or flakes of dried and graded woods adhered together. For LVL beams, thin wood veneers are bonded together into a billet, with the grain of all veneers running parallel to the length of the beam. Called “parallel lamination”, this orientation allows LVL beams to exceed the load‐bearing bearing capacity of similarly sized sawn lumber and be used for long‐spanning load‐bearing members, such as beams or rafters.
Parallel Strand Lumber (PSL)‐ Parallel strand lumber, another type of structural composite lumber, is manufactured using long, thin strands of wood (typically the waste material from plywood manufacturing), which are laid parallel and bonded together to form a billet. Similar to LVL members, PSL members can be used for long‐spanning beams where greater load‐bearing capacity is required. Additionally, PSL members are also frequently used as columns.
Laminated Strand Lumber (LSL)‐ Similar to PSL, laminated strand lumber is comprised of long, flaked wood strands of hardwoods not normally used for structural applications (e.g. maple). The wood strands used for LSL are typically shorter and thicker then those used in PSL, leading to lower load‐bearing capacity. Typically, LSL members are used for wall framing, such as studs and headers. LSL members can also be used for intermediate spanning beams and rim boards, where the higher strength LVL or PSL members are unnecessary.
Oriented Strand Lumber (OSL)‐ Oriented strand lumber is comprised of flaked wood strands strands very similar to those used in LSL member, but the length of the strand has been reduced and the thickness increased. As such, OSL members can typically be used in similar situations where LSL members are utilized
Glue-laminated lumber (also known as Glulam) is a versatile and innovative material widely used in the construction industry and has become increasingly more popular in recent years for its many benefits. Glulam is composed of wood laminations that are bonded together with high-strength adhesives to form a strong member.
Glulam members are customizable to be formed to specific lengths and curvature to fit the needs of most residential and commercial wood-framed properties. Most notably, in 2019, the construction of an 18-story building in Norway was formed from solely glulam and laminated timber beams. Glulam beams also have a much better environmental impact compared to steel or concrete beams for their carbon storage capacity. Furthermore, glulam beams have good fire resistance and can outlast steel beams due to a charred carbon layer that is formed on the surface of the beams which insulates against heat. In our industry, they are typically utilized to span large openings that regular timber beams cannot, like balcony door and breezeway openings.
While the benefits for glulam beams look to be impressive, the necessity of glulam beams over other engineered lumber beams may not be the most cost-effective solution, as the cost for glulam beams are higher than they are for many other engineered lumber. Deterioration of glulam beams is common due to high humidity areas and water intrusion through improper or unsealed flashings. While glulam beams are often marketed for their ability to be exposed to the natural environment, they are often very susceptible to deterioration due to construction methodologies. Glulam beams are prefabricated to an exact size; therefore, if the beams need to be cut to fit new dimensions, the entire beam can become susceptible to deterioration if the cut portions are not properly protected with a sealer material on-site.
Stroll down any street in Baltimore or Washington, D.C. and you are bound to find numerous brick buildings sporting a fresh coat of paint. The trend of painting brick facades has become popular over the last several years and while painting brick can provide an updated appearance, it may not be the best idea.
Brick masonry is naturally porous, meaning it contains small holes which allow liquid and air to pass through. Two common types of masonry wall assemblies we see locally are drainage wall systems and mass wall systems, both of which manage the water that inevitably enters through the porous masonry. Drainage walls contain an air cavity between the brick veneer and the back-up structure, allowing water to travel within this cavity and exit through flashings and weep holes. In comparison, mass walls contain multiple layers of brick masonry which rely on the wall thickness and bond between the bricks to resist water penetration into interior spaces. The majority of older and historic masonry buildings consist of a mass wall system.
Most paints readily available are not vapor permeable, more commonly known as breathable. Therefore, when paint is applied to bricks, they lose their porous nature which is critical for allowing evaporation in mass wall systems. The loss of porosity can cause any moisture that enters the wall system (through small cracks or other defects) or was present prior to paint application, to become trapped. This can cause bricks to deteriorate faster and can potentially trap moisture against interior framing elements, resulting in structural damage. Trapped moisture can also cause the paint to blister and flake, creating an unappealing appearance.
Additionally, masonry requires periodic maintenance. Painting brick can make it difficult to identify defects, such as cracked bricks and mortar, that should be repaired. Paint is also relatively permanent. Once brick is painted, removal can be very challenging and could result in significant damage to the brick walls.
However, there are options for updating the appearance of a brick façade, including brick stains and some breathable coatings. If you are interested in modifying the appearance of a brick structure and are looking for professional help, ETC can provide a solution.
Sometimes, differences in construction materials that might seem insignificant to the untrained eye can have long lasting implications and cause headaches down the road. ETC has seen this situation arise plenty of times when evaluating new below-grade drainage systems, specifically regarding the type of piping to be used: corrugated plastic pipes or rigid PVC pipes. Corrugated plastic pipes are thin walled pipes, typically .02” thick, with a series of grooves running parallel to each other along the length of the pipe, while rigid polyvinyl chloride (PVC) pipes are thicker, ranging from .1” to .5” depending on the diameter and schedule of the pipe, and have smooth inner and outer walls. Corrugated pipes are typically cheaper than PVC pipes and are easier to install and connect, making them a favorite of DIY-ers. However, in our experience, the increased flexibility and installation ease comes at a great sacrifice to the durability and effectiveness of the drainage system.
Corrugated pipes tend to clog more frequently then solid-walled pipes due to their ribbed profile and
are more difficult to clean as well, as an auger or plumbing snake could easily tear through the pipe’s
thin plastic walls. The thin plastic pipe walls are easily crushed as well, especially when backfilling with
compacted soils or stone. We have observed drainage systems where newly installed corrugated pipes
were crushed during construction, rendering a sizable portion of the drainage system useless from the
start. ETC always recommends rigid PVC pipes over corrugated pipes for below-grade drainage
applications in order to provide clients with an effective and durable drainage system. If you’re having
drainage issues and looking for professional help, ETC can provide a long-last solution to address your
needs. Contact us for a free proposal:
When most property owners think about ventilation upgrades, they often consider installing new windows and doors or replacing the existing HVAC equipment. However, they often forget to consider one of the most important locations within their building: the crawlspace. Improper ventilation can allow for humid air to become stagnant within the crawlspace, spurring microbial growth and accelerating the deterioration of both wood and concrete structural elements. Given the difficulty accessing the crawlspace, as well as the typical space restrictions, crawlspace structural repairs can be quite costly and lengthy, but proper ventilation upgrades can help curtail these repairs.
Allowing for adequate airflow is crucial for ensuring the longevity of the crawlspace structural elements. The International Building Code (IBC) imposes certain ventilation requirements given the size of the crawlspace area and other circumstances, such as climate conditions and crawlspace construction. In our experience, it’s not uncommon to find crawlspaces with either undersized vent openings or simply too few openings at all. Additionally, we typically find vents that have been covered with mulch or other landscaping, rendering the vent useless. The number of required vents can be reduced through the installation of fans within the foundation walls or the installation of a vapor barrier over the exposed crawlspace soils, given that the vapor barrier made of qualifying materials, properly installed, and in good condition. If you’re overdue for a crawlspace inspection, reach out to ETC to help evaluate your crawlspace today.
Wood-framed balconies can look sharp on a building, not to mention the comfortable outdoor spaces they can provide. One of the most important ways to protect your wood balconies and decks is to prevent water from deteriorating the framing. Deterioration typically occurs when water cannot properly drain and becomes trapped against wood surfaces. Consequently, this type of deterioration oftentimes occurs where we cannot see it!
A common location for deterioration on wood balconies is along framing members that connect to the
building (i.e. ledger boards, joists, etc.). Water often migrates behind these framing members and does
not have a way out. Additionally, frequent moisture in this location can deteriorate interior building
framing elements, such as wall studs or floor joists. This photo shows a building exterior following
demolition of wood-framed balconies. The deteriorated exposed framing on the left-hand side shows
why it is so important to protect wood framing from trapped water. What is the important difference
between the left and right sides?
A metal flashing was installed along the original balcony framing on the righthand side, but not the left. Flashing is an impervious material, such as metal or plastic, that prevents water from intruding to an interior space by providing an alternate drainage path (see the sketch below from FEMA Home Builder’s Guide to Coastal Construction Technical Fact Sheet No. 24 for a typical ledger flashing detail). After more than 30 years of exposure to the elements, we can see how flashing played an important role in protecting the wood framing of the building shown.
As the hurricane season is fast approaching, it makes sense to have an architect and engineer look at possible areas of damage/water intrusion in your building. This is the perfect time to address these issues before any damage is caused to your building due to heavy rains and/or high winds.
Here is a list of areas to inspect before the next rainstorm.
- Site Grading; Making sure that the soil is sloping away from the building;
- Building and Site Drains; Ensure that the drainage provisions (such as roof gutters, downspout, landscape drains) are clear of debris and are operational. If the gutter terminates at the building foundation, consider extending it away from the building.
- Exterior Cladding; Ensure that the building facade components are adequately secured to the building, such as gutters, downspouts, metal coping, canopy, cornices and are not loose or partially detached.
- Sealants; Ensure that an excessive opening in the sealant joint is visually inspected and repaired.
- Roofing; Inspect roofing membrane and associated components (joints, penetrations, parapet wall caps, chimneys, etc.) to help assure that these components are intact and watertight.
The wind driven rains can be very unpredictable and can cause damage. However, larger damage to the building can be avoided/minimized, if the above mentioned areas of concern are addressed before a major rainstorm.
Retaining walls offer a mix of form and function. A retaining wall can hold back the soil behind it, playing an important role in preventing erosion, particularly on hills or in areas where plants can’t grow. Retaining walls are also used to create flat, usable ground on hilly terrain for things such as parking lots and sports fields. A retaining wall can also enhance landscape designs. For example, a landscape architect or designer might build retaining walls to create different levels of terrain or different elevations in a garden.
Retaining walls differ from the walls that hold up a building or another structure. While the walls of a home or apartment building are designed to support vertical loads such as ceilings and roofs, retaining walls are meant to support horizontal loads. For that reason, the design and engineering of a retaining wall differ from the design and engineering of the wall of a building.
While there are similarities in the types of materials used for building retaining walls and other types of walls, some materials are better suited for use with retaining walls. In this guide, we’ll take a look at some of the most commonly used materials for retaining walls.