Basements

These spaces within the home have changed drastically over the past several decades. Areas that were once used only for storage and laundry have been transformed into full living spaces, barrooms that would put the Hard Rock to shame, playrooms or general recreational areas. What a wonderful thing, to pickup all this additional living space that is already in place. But there are some hidden and outward problems that are common in basements. Listed here are some of the problems, as well as explanations of what is used to create these spaces.

Moisture seepage

This is, not only common, but quite regularly found in basements that we visit. The main 2 reasons that moisture makes its way into a basement are related to the exterior grading and the lack of a properly drained gutter system.

• Exterior Grading
  • When soil around the perimeter of a house is pitched back towards the building, this allows water to pond against the foundation, which eventually travels downward.
  • The inward pressure against a foundation wall increases as it gets closer to the bottom of the basement, and this helps “push” water through the wall.
  • The simplest solution is to “raise the grade” of soil outside the building. This means adding dirt around the perimeter of the foundation to create a positive slope away from the building. This way, gravity will help drain runoff away where it is less likely to enter the building.
  • One note of caution – make sure you do not allow this buildup to come within 6 inches of the siding, as this will create another problem, namely wood rot and wood destroying insect damage.
• Poorly drained gutters
  • Gutters that are plugged with leaves and debris can back up and run down the siding to the base of the house. In the winter, this condition can also add to ice damming issues.
  • Gutter downspouts that lack extensions, or “leaders”, also deposit water against the foundation. This is why most basement seepage is found near the corners.
  • We always recommend that leaders be extended a minimum of 6 feet away from the building.
  • Another note regarding downspouts; if they are depositing roof runoff on to a sidewalk or driveway surface, this will cause premature wear, deterioration and settlement. This is very important, as over time the water can erode the foundation blocks and may cost thousands of dollars to repair in some instances.

Foundation cracks

There are a number of different types of cracks that may be found in a basement or crawl space. Listed below are a few, and an explanation of the usual cause.

• Horizontal cracks
  • This type of crack generally occurs when a foundation wall is being pushed inward, most often because of hydrostatic (water) pressure.
  • If these cracks are wider than a pencil eraser, they may be a cause for concern, and should be further checked by an expert.
  • Narrower cracks should not be ignored, but sealed with mortar and monitored over time. If the cracking reappears, that would indicate continuing movement, and would require further evaluation by a structural expert.
• Vertical cracks
  • These cracks are often referred to as “settlement cracks”. They occur when the material that the wall is bearing on (the footer) settles. It is not entirely unusual to find small hairline settlement cracks that appear within the first year of the life of a house.
  • The big concern is this:
    • Is it a one time minor settlement?
    • Is it an ongoing settlement issue that requires further exploration, and possible structural repair?
• Step cracking
  • This is simply another type of settlement crack where, for instance, a footing below the corner of the foundation sinks, and the block wall above shifts along with it.
  • In some cases, the cracks will display a visible difference, being larger nearer the top or bottom. This is how to determine whether the settlement occurred near the center of the wall or near the corner.

Types of floor framing

• Traditional dimensional lumber
  • These are usually 2x8’s or 2x10’s; with occasional 2x6’s found in some areas. (2x6’s are generally considered to be undersized in most cases of modern framing depending on the span.)
• Floor truss systems
  • This system is designed with a 2x4 at top and bottom, with steel webs throughout the middle, providing strength. They were used for a short while in some housing tracks back in the late 1970’s through the 1980’s. They are still available today, but are not widely used.
• I-Joist flooring systems
  • One of the newer marvels in floor framing, these items are, simply put, a web of ½ inch plywood or OSB (Oriented Strand Board) that is notched into a 2x2 at top and bottom. Since they are engineered, they provide a flat surface, without the warping or crowning of dimensional lumber.
  • They are also advertised as providing a squeak-free floor system.
  • Care should be used when boring holes through the center of these joists, as there are specific tolerances that must be followed to prevent losing the structural integrity of the joist.
• Laminated flooring systems
  • Laminated lumber is designed to provide greater strength per foot that dimensional lumber. As it is also engineered, it provides a flat smooth floor, and will span farther, limiting the need for as many supports.
• Hand hewn or simple logs
  • This type of joist is usually found on houses built pre-1900’s and on occasion, log or rustic-design homes.
  • This work was all done by hand by a carpenter and a tool called an adz. It’s uncommon to find a house of this vintage that doesn’t have sloped and/or sagging floors.
  • Quite frankly, the floors were probably not flat even when the house was constructed.
  • Except in extreme cases, floor jacking is generally not recommended, as the floor has no memory of what "flat" is. It often results in a hump in the floor where the sag used to be. This may also cause damage to the wall finish in the rooms above.
  • It may be necessary to install simple support beams underneath some areas just to eliminate bounce and prevent further sag.

Beams

• Built up wood beams
  • These are nailed, and often, affixed together with construction adhesive. The size of the lumber is determined by the architect and there is commonly found ½ plywood nested between the boards.
• Solid wood beams
  • These are usually hand hewn, and often are mortised to accept tenons from hand hewn floor joists in older houses.
  • Another style of solid beam has a ledger board nailed into the bottom edges. This style will have the floor joist notched to rest atop the ledger. It is not uncommon to find ledger boards pulling away from the beam, causing sagging.
• Steel I-Beams
  • These beams are set in place by a crane and are very common in houses from the 1950-70’s, though are still used today.
• Laminated wood beams
  • Often referred to a LVL’s, or Laminated Veneered Lumber, this type of engineered beam is becoming more and more common in modern framing, as they are available in virtually any size and are known for being able to span greater distances than dimensional lumber, without the use of as many supports.

Support columns

• Wood support posts
  • Often found in houses built in the early part of the last century and prior, these were simply logs that were put in place to support the main beam. Their number one drawback is they have sat in moisture over the years, and are commonly rotted at the base.
  • They are also attractive to insects.
  • It is common to find these having been replaced by steel columns.
  • From time to time, pressure treated 4x4,or 4x6 supports are found in newer construction, although this is not a common find.
  • It is important that these are secured at both top and bottom.
• Steel columns
  • Sometimes referred to as “jack-posts” These began appearing in the 1930’s and are used extensively in modern floor framing. They are designed to carry the weight of the main beam.
  • They should not be confused with split-adjustable posts mentioned below.
  • These should also be secured at top and bottom.
• Split adjustable columns
  • These posts are similar to their big brother, the steel column, although are commonly misused. They are designed as area supports and are not engineered to carry the weight of the main beam.
  • These are identified by the two-piece sleeve that has metal pins inserted through holes.
  • They are rated to carry somewhere around 3500 lbs. whereas the steel columns are rated for around 20,000 lbs.
  • That is not to say that if enough of these posts are installed they won’t do the job, they just weren’t designed for main supports.

Basement floors

• Concrete floors
  • Found in most basements.
  • Hairline cracking is not uncommon.
  • Control joints will usually lessen cracking
  • The concrete floor is generally not a structural component of the house
• Drainage systems
  • Most basements have either a sump pump or a floor drain
  • SUMP PUMPS- These pumps are installed inside a sump crock which is a fancy name for a pit in the floor where a plastic tub is installed.
  • Often, the under-floor drainage system is tied into this pit through a series of perforated pipes. These pipes pick up the water that seeps around the perimeter of the basement, and channel it into the pit where the pump ejects it to the outside.
  • It is a good idea to have this pump wired to its own circuit.
  • Most sump pumps last around 10 years, unless they are under mucky conditions, in which case failure is often sooner. Replacement should be proactive to eliminate the risk of finding out too late that the pump has gone haywire.
  • A sump pump crock cover is a good idea, as it helps prevent folks from falling into the pit, as well as assists in controlling moisture.
• BACK UP SUMPS
  • There are a few different options here. One would be a battery operated system, which is powered by, you guessed it, car batteries.
  • The other type (which we prefer) is a water driven pump that operates off of your public water system. Sure, you lose water when this is running, although it’s usually much cheaper than replacing the damaged goods in the basement if it floods.
• FINISHED BASEMENTS:
  • If you plan on converting your basement into a finished area, ensure part of that process includes providing a secondary ext in case there is a fire in or near the stairwell. This is a must when finishing a basement
  • The most common form of secondary exit we come across is called an "egress window", such as seen in the photo