A two story house should adhere to more local building codes than a smaller home with just one floor. Additional residential building regulations for the second story or floor are partly influenced by the specifications of the first or ground floor, footing, foundation, and other factors.
A two story house with a flat roof is 18 to 20 feet tall. Two story houses with pitched or sloped roofs are taller and can be as high as 35 feet with attics, lofts, or other constructions and installations atop the second floor.
Most local building codes mandate a two story house to have a minimum height of 16 feet due to the necessary ceiling heights of habitable spaces. This article discusses the relevant codes and specific factors dictating and influencing the height of a two story house. Keep reading.
Two story Cape Cod homes are usually shorter than Victorian houses. Likewise, a craftsman’s home is generally not as tall as a colonial-style house. Traditional ranch homes with two stories tend to have lesser elevation than Mediterranean-style houses.
Contemporary styles are typically minimalist and prioritize efficiency, whether for energy consumption or space utilization. Hence, they aren’t very tall compared to older or traditional styles. Furthermore, geography and climate influence the general height of two story houses.
Low-lying and flood-prone zones may necessitate two story houses to have a more raised first or ground floor. Thus, these homes will be taller than those with lower ground floor profiles.
Similarly, a two story house with a basement may be taller than usual, depending on how much of the latter is aboveground. Even identically styled houses can have slight variations in height depending on the type of frame, construction materials, and roof pitch.
The height of a one or two-story house is measured as the linear vertical distance between the finished grade on the ground and the roof’s highest point, excluding removable installations such as satellite dish, antenna, skylights, and chimney, among others.
A story is about 10 feet tall, including the aboveground foundation or footing, ground floor depth, ceiling height, and flat roof. Typically, a story is taller for houses with pitched roofs, higher ceilings, thicker foundations/footings, and floors with more depths.
A residential story has a foundation or footing, usually both. The first or ground floor ceiling or roof is the base or foundation of the second story, and the other components are floor depth, ceiling height, and roof thickness. Each of these components must abide by the local building codes.
Conventionally, an aboveground foundation or footing is around 1 foot, and a floor also has almost the same depth. The typical ceiling height is 8 feet, and a floor or roof above is usually up to 1 foot. Hence, a story is roughly 10 feet tall.
However, there are numerous variations throughout the country. Many houses tend to have a higher ceiling for the ground floor than the second story. Also, some homes have higher than usual ceilings. Thus, it’s practically impossible to use one figure as the default standard.
The International Residential Code’s minimum ceiling height for any habitable space or room is at least 7 feet. Thus, the first or ground floor must have a height of more than 7 feet, especially if you wish to have a drop ceiling or more headroom for fans.
Most states in the US have adopted most of the regulations of the International Residential Code. Hence, your local building regulations include this minimum ceiling height in all likelihood. However, many local codes are slightly different, so do check the regulations as you plan.
Take the example of Florida. Like many other states, Florida permits the construction of tiny homes. According to the Florida Building Code (Residential), the minimum ceiling height for tiny houses is 6 feet 8 inches. Thus, a one or two story tiny house can be shorter.
Those designing a blueprint for any story or floor should refer to the local building regulations because they supersede the International Residential Code. Besides, states have demarcated residential areas, such as low-lying, flood-prone, and hurricane zones.
The second story or floor must adhere to the same building code. It must have a minimum ceiling height of 7 feet. On the other hand, the second story ceiling can be identical to the first or ground floor. Also, it may be slightly shorter or taller, but you can’t have a huge disparity.
Generally, homeowners prefer a taller first or ground floor ceiling, which could be anywhere from 10 to ~14 feet. And, the second floor or story could have a shorter ceiling at around 8 to 10 feet. However, attics and lofts are distinct categories.
A loft occupying only a portion of a second story and not the entire floor can have a shorter ceiling; however, it must have the minimum area to be considered livable or habitable space. For tiny houses like those in Florida, a loft may have a ceiling shorter than 6 feet 8 inches.
However, the Florida Building Code has stringent conditions determining what qualifies as a loft. For instance, a loft with a sloped ceiling reducing the height to less than 3 feet will not have that part of the floor counted in the qualifying habitable area, except for gable roofs.
Thus, the ceiling height of the second story or floor in residential houses depends on many factors. A loft in a tiny house can have a 6 feet tall ceiling. In contrast, a second story with bedrooms, bathrooms, and living spaces can be taller than 10 feet.
All states have building codes necessitating minimum ceiling heights for bedrooms, bathrooms, kitchens, living spaces, hallways or foyers, attics, lofts, and other areas. Generally, hallways and foyers should have a minimum height of 6 feet 6 inches. Nondescript areas or remaining spaces should be at least 5 feet tall. Of course, you can plan upward.
Bedrooms, bathrooms, kitchens, and living areas are in the habitable space category, so all should have a minimum height of 7 feet, be it on the first or ground floor, a second story, or subsequent levels. Also, any ducts, beams, and other installations on the ceilings of habitable spaces should not reduce the net height to below 6 feet and 4 inches.
Therefore, a standard second story with bedrooms, bathrooms, and other living spaces should have a minimum height of ~10 feet if you include the floor depth and roof thickness. The first story is effectively taller due to a portion of the foundation or footing depth.
Every architectural component, be it the foundation, footing, ground floor depth, ceiling heights, and type of roof, has a proportional effect on the eventual height of a two story home. Also, topography and selected construction materials are significant factors.
A two story home with a substantial aboveground foundation will be taller than a house with shallow footing. Likewise, houses with greater floor depths and thicker roofs will be taller. Also, the type of roof, whether flat or pitched, will decide the highest point of a two story home.
You must consider the incremental effect of each of the architectural components that are fundamental to a two story home’s structural integrity and sustainable construction. Such a calculation will illustrate how the ground realities affect the height of a two story house.
Let me use the following specifications for our calculation:
- Aboveground foundation and footing depth: 1 foot (0.3 meters)
- First or ground floor depth: 1 foot (0.3 meters)
- First or ground floor ceiling height: 9 feet (2.74 meters)
- First story roof or second floor depth: 1 foot (0.3 meters)
- Second story ceiling height: 8 feet (2.44 meters)
- Flat roof & subfloor depth on the second story: 1 foot (0.3 meters)
The height of this second story house is 21 feet. However, a pitched or sloped roof will increase this height by a few feet. Also, an optional loft or attic with a height of, say, 7 feet will affect how tall a two story home is. Replace the second story ceiling height with the loft’s if it is the only construction on the floor, or add if it is on the third level.
The first component determining the height of a two story house is the foundation and footing. All footings are a type of foundation. However, all foundations are not footing. The foundation and footing depth depends on the topography, soil type, and house design.
A two story house may have a foundation under the basement, or it could have a slab on grade. Also, two story houses may have a crawl space that will influence the eventual height. Furthermore, each of these styles has variations, a few of which are mandatory due to codes.
You may read the International Building Code – Chapter 4: Foundations for a comprehensive understanding of how distinct styles, soil type, materials, and footings affect the depth, and thus the height of the base of a house. Your local building code may have a few more regulations.
Essentially, the foundation and footing depth should be greater for two story homes than houses with only one floor. Also, the depth is inversely proportional to the soil’s load-bearing capacity. Furthermore, every type of slab used for foundation and footing has specific requirements.
In effect, a two story house with a larger foundation and footing above the ground will be taller than others. Homeowners may choose a sturdier foundation and footing, thus paving the way for more robust construction. Also, poor soil or ground conditions can necessitate the same.
The construction materials have an unavoidable effect on the eventual height of a two story house. You may use concrete, crushed stone, gravel, or a combination of materials for the foundation, depending on the topography and soil. Each of these materials has different codes.
Also, the specific width and depth of the foundation and footing based on the material you have to choose and the type of frame you want for a house will decide the applicable codes. For instance, the dimensions vary for concrete, brick veneer, masonry, and wood. Furthermore, there is a vast difference between heavy and light-frame construction for all types of properties.
Flat roofs are simple, and they don’t significantly increase the height of a two story house unless we consider the optional parapets used in warmer regions. Pitched or sloped roofs can substantially affect how tall a two story house is due to their varying types and designs.
Open gable, box gable, and dormer roofs may have similar heights, but a dutch gable could be taller. Likewise, hip or cross hipped and intersecting or hip & valley designs may have identical peaks. However, gambrel, saltbox, mansard, and skillion may have varying peaks, thus heights.
The type and design of the roof determine both its depth and the zenith. Also, the preferred roofing options weigh heavily on the blueprint for a two story house. The roof should not be an afterthought as the second story ceiling height and other details must suit the preferred designs.
Hence, the final height of a two story house can increase substantially if a homeowner chooses a taller roof with a higher peak. This increase can be even greater if the roof has a steeper slope due to the size of a house or a selected design. Also, local regulations will influence the specs.
Like the minimum specifications per the International Residential Code, local building regulations may have maximum limits on various single and multi-family dwellings features. You may live in an area where a two story house cannot exceed a certain height. Thus, always refer to the local codes while planning and finalizing the blueprint.
A two story house must be reasonably taller than the minimum requirements to make room for HVACs and drop ceilings. Also, you may need fans, smoke alarms, sprinkler systems, ducts, and beams. Besides, more headspace or room may simplify potential remodelings in the future.