Windows | Door | Building Science / Envelope and More

What do I mean by “new construction” and “replacement” windows? The way most people understand the difference between the two is that new construction windows utilize a nailing flange (fin that protrudes out from the window frame surrounding entire perimeter of the window) to install the windows and replacement windows have NO nailing flange. This over simplification of these terms often leads to buying the wrong product and poor installations. However, for the sake of mutual understanding, when I use those terms assume that is what I mean.  Nailing Flange Around Window Frame 1st Myth: When replacing windows, always use "replacement windows" - aka no nailing flange. It’s actually almost the exact opposite. Replacement windows should almost always HAVE a flange for installation.  The only times I would deem it acceptable to replace a window withOUT a flange is twofold: 1. Your house was build pre 1945 and you have the old sash weight wood double hung windows. For installing ne...

  If you are familiar with construction, then you may know that measuring and ordering windows can be complicated. Whether they’re for a new construction house or a replacement project, it’s crucial to know the difference between “RO” sizing and “net” sizing.   Rough opening (RO) size is simply the framed opening size. Meaning after a window is framed by the framer, the width and height of the stud to stud measurement is the RO dimension. Net size (also called frame size or heel size) is the actual width and height of the window from outside edge to outside edge. New Construction: If you’re building a new house then windows are always part of the equation. Looking at blueprints it may seem obvious what the sizes are - especially if there is a window schedule. However, there can be some confusion about what the ACTUAL size of the windows will come.  The important thing to know is that all specs related to window sizing on house plans is always the RO size.   2850 = 2'...

Thermal Bridge vs  Thermal Break If you’re new to building science these terms may seem esoteric but hopefully you will come to a better understanding of them after reading this.  Think of the term thermal as HEAT .  Think of term bridge   (in thermal bridge) as a connection between point A and point B - which is what an actual bridge is. So thermal bridge is simply the act of heat transporting through or on the “bridge” from point A to point B. Think of the word break (in thermal break) as in shutting down a lane of traffic on that “bridge.” Now it’s a one lane road, cars are going much slower and there is a greatly reduced number of vehicles crossing. During peak hours more cars might travel through then other times of the day. But nonetheless there has been a great interruption. In terms of heat transfer (or thermal bridge), once a thermal break is incorporated, heat (and cold) has a much harder time traveling from point A to point B.  Heat/...

CLAD WINDOWS Clad windows simply refers to the different materials “capping” the wood window so that it becomes more durable and less likely to rot. Many window manufactures design a wood interior, clad exterior window. Often times there are interior wood specie options as well  as different exterior cladding choices such as vinyl, fiberglass and aluminum. I will be focusing on an aluminum clad exterior in this post. There are a number of aluminum clad wood windows on the market and they are not all created equally.  When comparing various manufacturers to one another, it is important to understand the differences in materials and construction that windows are made out of.  The aluminum exterior is made in one of two ways: roll form or extruded. HOW THEY ARE MADE ROLL FORM The roll forming process uses a pair of rolls to fabricate the metal. Metal sheets are passed through the rolls several times until the desired shape or profile is achieved. EXTRUDED The extruded alumin...

Ice & Windows If you live in a house with original aluminum or single pane windows, then your house was built prior to 1970 when double pane windows became more widespread. In colder climate zones, a common problem that arises during the cold winter months is ice forming on the inside of their windows, on the actual glass. Other typical issues people experience are. the frames “sweating” (which is related to this topic), being hard to open and drafty (which is also connected to the topic of icing up).  Does your window look something like this…  Ice on old wood single pane window Why Does This Occur? Ice comes from frozen moisture/water vapor so then the question turns into, why is there moisture on the inside of my windows? It stems from interior humidity (aka water vapor in the air) trying to escape to the outside of your home. It finds the path of least resistance which would be your windows or through the glazing. When it hits the window frames and/or glass, the water...

Everything Makes, Absorbs or Blocks Sound Every animal, object, and thing does one of those three things. Animals and humans all make sounds. Snow & furniture in a house absorbs sounds (think about how much a house echo's when it is completely empty). Retaining walls and house walls block sounds, and windows also block sounds... but how effective are they?  Windows Do Many Things Windows are a crucial element to a homes overall appearance and performance. They are a major design component that ideally matches the style of the house. Then they also serve an important role in regards to energy efficiency... they block out solar heat (or let it in depending on if you have a passive house), they reflect the heat back into your house during winter months, the block out harmful UV rays and of course they let you look out into the beautiful world. If you would like to learn more about windows NFRC ratings and their purpose,  see my post about windows NFRC ratings . Another key el...