Window and plywood question

[rubio_higuey]

OK guys, thank you everyone. Throughout my life I have worked much more with my brain than with my hands, so DIY is not my type of thing though I have done some pet projects in the past.

Anyone could please explain to me in more detail, how to go about it (attaching plywood to the bars)? What are 2x4 and washers?

Let's say I bring the plywood to the height of the bars, how would I attach that plywood that is outside, by doing it from inside?

 

[ju10prd]

Windows and glazed doors normally fail in hurricane conditions due to pull out due to the negative pressures exerted externally to structures and the main mode of failure is the fixings of frame to wall.

Often the window unit remains intact as shown by the window units to Richard Bransons house in Neckar, BVI where his intact window units were found up to 40meters away from the buildings.

The other mode of failure is the glass through impact or pull out of the frame which is far less likely.

That is why you ply board over the opening with ply fixed to the wall to eliminate the negative pressure effect and also avoid impact damage.

Much depends on the quality and size of your glazed. Small windows are surprisingly strong if they have been fixed properly with sufficient and correct length and quality fixings. Go check the number of fixings used. For smaller and even larger glazed units taping can be effective especially if the builder was so cheap and used single pane float glass which many do here in DR and is dangerous.

If you have a 4mm plus 4mm laminate glass you will probably be good for most storms we get here without boarding, and if you have 6mm plus 6mm laminate it can survive even Irma as a local supplier confirmed this week about his supplied glazed units in a hotel in Anguilla.

Being higher up, impact damage seems less likely but look what is around you. Fixing on the outside to the iron bars does not stop the pressure pull effect but does stop impact damage.

 

[cobraboy]

Ideally, the plywood should be attached flush or almost flush with the wall. Maybe hang on to a set of bars and lift your feet of the ground. If the bars move at all, attaching plywood to them is not a good idea. Hard to know what to do. A lot would depend on wind speed, direction, duration and luck in determining if what you propose would be of more result in more of a benefit than potentially increasing the possibility of damage.

An ounce of prevention...

When I purchased properties in FL, one of the first things I did was prep them for hurricanes. In good weather. Without panic.

I took a different route. I would cut 1/2" plywood at least 8" beyond the windows and doors. I would mark the plywood and drill holes into the concrete block walls large enough to accomodate a strong SS lag bolt & lead shield. The hole would be slightly countersunk so the lag bolts and washer would be nearly flush with the surface. The bolt head and washer got painted the same color as the block. You could barely notice unless you got really close.

I would then completely paint each plywood panel with epoxy paint, and each panel was maked for window, door and position. The reason being storing plywood in a humid environment will lead to delamination and warping. An epoxy barrier largely prevents that from happening. It also kept the plywood from becoming saturated in the storm rain.

Each house took a couple of days to design and install.

I had a storage unit just to store the plywood panels for all the houses, the cost spread over several units.

When a storm came it took very little time to pull the panels out of storage and install them in the house. Everybody else was scampering around in a panic and dealing with supply shortages and high prices, with time slipping through the hourglass. Not me. In one day I could prep all six houses.

When I sold the houses, a HUGE selling point was the storm preparation. The incease in price was way more than the cost of installation. AND the houses sold quickly. Purchasers stated that a prime motivator was the storm prep.

I often thought about a business model based on a storm prep service using fiberglass panels instead of wood, kinda like a home alarm servive where a clent pays for installation, a monthly fee for storage, and a fee for storm installation. I'd contract with tradesmen for installation & removal.

 

[cobraboy]

Windows and glazed doors normally fail in hurricane conditions due to pull out due to the negative pressures exerted externally to structures and the main mode of failure is the fixings of frame to wall.

Often the window unit remains intact as shown by the window units to Richard Bransons house in Neckar, BVI where his intact window units were found up to 40meters away from the buildings.

The other mode of failure is the glass through impact or pull out of the frame which is far less likely.

That is why you ply board over the opening with ply fixed to the wall to eliminate the negative pressure effect and also avoid impact damage.

Much depends on the quality and size of your glazed. Small windows are surprisingly strong if they have been fixed properly with sufficient and correct length and quality fixings. Go check the number of fixings used. For smaller and even larger glazed units taping can be effective especially if the builder was so cheap and used single pane float glass which many do here in DR and is dangerous.

If you have a 4mm plus 4mm laminate glass you will probably be good for most storms we get here without boarding, and if you have 6mm plus 6mm laminate it can survive even Irma as a local supplier confirmed this week about his supplied glazed units in a hotel in Anguilla.

Being higher up, impact damage seems less likely but look what is around you. Fixing on the outside to the iron bars does not stop the pressure pull effect but does stop impact damage.

You are correct: the negative pressure does more damage that flying objects. Once one opening is breached, a real mess will occur.

 

[rubio_higuey]

If you have a 4mm plus 4mm laminate glass you will probably be good for most storms we get here without boarding, and if you have 6mm plus 6mm laminate it can survive even Irma as a local supplier confirmed this week about his supplied glazed units in a hotel in Anguilla.

I am renting and the building is quite old ... I have no way to find out what glass was used ... I guess whatever most people used when they were building 15+ years ago.

 

[Cdn_Gringo]

2x4 = a wooden board (not plywood) that is 2 inches thick by 4 inches wide.

Washer = a metal disk with a hole in the middle that a bolt goes through to increase the holding strength of the bolt without biting into the plywood or the 2x4 weakening the holding power of the nut & bolt or making it difficult to later remove. You'll need a washer for the outside and inside for every nut and bolt you use. Slide the bolt through outside washer, then slide bolt through plywood and the 2x4 you are using to hold everything in place then slide on another washer than add and tighten the nut.

 

[rubio_higuey]

OK, found the video

[video=youtube;LBU7gCyx2_A]https://www.youtube.com/watch?v=LBU7gCyx2_A[/video]

But where would I put the 2x4 piece of wood? Inside the house, or between the window and metal bars?
Because
1) if inside: windows would need to stay open (unless I would use two long bolts on the sides and leave windows open just a bit both on the right and left
2) if between the bars and window: where exactly would I put this 2x4 piece of wood? It's not like it's going to stay in the middle, unless its somehow affixed to the middle horizontal rail of the metal bars ... but what would I use to affix it there?

 

[rubio_higuey]

OK, found the video

[video=youtube;LBU7gCyx2_A]https://www.youtube.com/watch?v=LBU7gCyx2_A[/video]

But where would I put the 2x4 piece of wood? Inside the house, or between the window and metal bars?
Because
1) if inside: windows would need to stay open (unless I would use two long bolts on the sides and leave windows open just a bit both on the right and left
2) if between the bars and window: where exactly would I put this 2x4 piece of wood? It's not like it's going to stay in the middle, unless its somehow affixed to the middle horizontal rail of the metal bars ... but what would I use to affix it there?

 

[Cdn_Gringo]

The 2x4 bracing goes across the inside of your window frame and extends 4 - 6 inches either side of the frame along the wall. Yes, unfortunately, you have to leave your windows open. As you say if you secure two bolts close to the frame you can partially close your windows. If it were possible and more feasible to use a single bolt in the centre of the window to hold everything you would not be able to close the window much if at all.

 

[ju10prd]

I am renting and the building is quite old ... I have no way to find out what glass was used ... I guess whatever most people used when they were building 15+ years ago.

Look at the size of the panes of glass first and surrounding area.

If you have small panes it might not be needed to worry so much about glass pullout and impacts.

My main focus would be on the number of fixings of frame to blockwork/concrete. I just checked the fixings of a 3metre by 1metre high unit I have in my rented place and we have two rusty pairs of fixings across the length of track which is hopeless.

I doubt if fixing plywood of any thickness to bars offset from the windows will be any use. Look at the balcony doors first.

 

[rubio_higuey]

My largest windows are 47x42 inch, others are 16x45 inch. Balcony door is from wood.

 

[rubio_higuey]

The European Windy model has me scared... shows the eye passing by right SW of Higuey.

I decided to buy tomorrow 5 plywood tables, 3/4, they do not have "exterior plywood" specifically here, but they say this one is used to pour concrete roofs over them (so I guess they should withstand some pressure).
4x8 foot, 3/4 inch wide table comes at 1750 pesos, I guess I would need 5 of them as per measurements I did and 1-2 or 3 2"x4" wood tables (they come 16 feet long, so i would ened to calculate how many I need)

I do not want this to be a one-season job, so I would want to paint/treat them so they can hold for several years (storing them inside).

Does anyone know how should I go about painting/treating this plywood so it can hold good for use for several years?
What type of paint or treatment to put it through?

P.S. I have two windows that are shielded, in term that they are on the side of building and there is another building right across from those windows, there is about 5-6 feet wide "callejon" between my building and thsi other building. Would these windows need to be boarded up as well or would the fact that the wind cannot blow on to them directly, make them less vulnerable

 

[DR Solar]

The European Windy model has me scared... shows the eye passing by right SW of Higuey.

I decided to buy tomorrow 5 plywood tables, 3/4, they do not have "exterior plywood" specifically here, but they say this one is used to pour concrete roofs over them (so I guess they should withstand some pressure).
4x8 foot, 3/4 inch wide table comes at 1750 pesos, I guess I would need 5 of them as per measurements I did and 1-2 or 3 2"x4" wood tables (they come 16 feet long, so i would ened to calculate how many I need)

I do not want this to be a one-season job, so I would want to paint/treat them so they can hold for several years (storing them inside).

Does anyone know how should I go about painting/treating this plywood so it can hold good for use for several years?
What type of paint or treatment to put it through?

P.S. I have two windows that are shielded, in term that they are on the side of building and there is another building right across from those windows, there is about 5-6 feet wide "callejon" between my building and thsi other building. Would these windows need to be boarded up as well or would the fact that the wind cannot blow on to them directly, make them less vulnerable

I'm pleased that you have made your decision, planning and doing. That's a big step. I hope that you have enough information provided above that implementing is part of the known plan.

Sealing the wood? I don't know what specific products are available but I know that I had my guys get some epoxy type sealer for a smaller project with plywood. The 2X4s are usually pine and rough grade should be fine saving some expense but knowing that insects and rot may happen. I use the end cuts of the 2X4s to lay down 2 lines to stack my plywood at an upright angle during storage so they are not in direct contact with the ground/cement to keep them dryer and allows ventilation and access to spay insecticides under, behind and the sides. Mine are in a covered area and marked for location when/if needed again. These should last for years if prepped and stored properly.

Remember that the winds will shift from one side to another but not all sides will get hit with the big winds. You have to determine where the lesser sides are but even those will get some. For me, being on the north coast on the ocean, I look at my northern and western sides as getting hit the hardest. The eastern side I do a little and the southern side none. But most of my windows are thick double glass and arched bay type or set back and protected more.

Good luck and again... feel good about you making progress.

 

[Cdn_Gringo]

I'd recommend a varathane/poly-urethane clear or coloured. You will probably need at least two coats as the plywood may soak up much of the first coat. You may not have time for two rounds of painting before the storm arrives. Put up your plywood and deal with the waterproofing after the storm and the boards are completely dry.

Before waterproofing, dry the wood completely by leaning it against the sunny side of a building for half the day and then turning them around so that the other side faces the sun for the rest of the day.

 

[DR Solar]

The outside perimeter edges are what really need to be sealed the best. That's where the moisture and insects and rot start and delaminate the layers of plywood. In the U.S., I used Smith & Company two part epoxy that when on like water and was clear on my antique boat and later on my antique house. It was great!

Point is to seal the "end grain" as best you can until it will not take anymore of the epoxy sealant. The long grain/main surface usually only needs a couple of coats.

(why do I feel like I'm in a "one upsumship thread"?)

 

[ju10prd]

My largest windows are 47x42 inch, others are 16x45 inch. Balcony door is from wood.

I was looking through Miami Dade code ( the code used by designers in the Caribbean for wind load design) to see if I could offer any advice on window fixing positions but it comes down to window manufacturers and window size. A good guide is to check if your windows have fixings spaced between 8"and 12" all round. If not start by securing them better.

I assume your windows are broken into panels. What is the largest size of glass is more the question.

The most likely failure will be the fixings or lack of them and then impact if they are normal size glazed panels.

Always good to have hurricane shutters as part of your building and friends that have included that in their home design have an easy time when a storm threatens and in less than half an hour it is all closed up. Having shutters gives peace of mind.

 

[Catseye]

Speaking of hurricane shutters, anyone know a reasonable place to get them here?  I'm thinking the electric roll up ones.

 

[ju10prd]

Speaking of hurricane shutters, anyone know a reasonable place to get them here?  I'm thinking the electric roll up ones.

You might like to consider this fabric option.

http://www.hurricanefabric.com/index.php?main_page=subcategory&pid=1

 

[rubio_higuey]

One more question:

Plywood attached to bars fitting the window frame, with 2x4 wood bar inside the room, bolted across the window frame, as mentioned this would require windows to be left partially open, opening up possibility for water to enter inside through the openings between plywood and the window frame (plywood - bars - window - 2x4 inside).

So would this be preferred option to using a 1x4 wood bur placed inside the frame, just after metal bars but before the window, I believe the bars are strong enough, and the 1x4 placed between bars and window and bolted across bars with plywood outside of the bars would allow for windows to close. (plywood - bars - 1x4 - window).

Though I understand 2x4 is safer against wind and stronger, because the extra length the 2x4 provides from inside uses the strength of the wall to hold onto the plywood, and not just the strength of the bars which would be the case when using 1x4 in between bars and windows.

But what about the water... I don't want to be protected against winds but then found flooded through the openings on the side of plywood (using plywood cut to the frame of the windows as shown in the video).

???

So many factors to ponder ...

I want to go buy materials tomorrow, and what I buy will depend on what you guys suggest ...

 

[Catseye]

You might like to consider this fabric option.

http://www.hurricanefabric.com/index.php?main_page=subcategory&pid=1

thanks, that stuff looks interesting, I could supervise my gardener and do it myself, so to speak

I kinda wanted something by Wednesday, though, I'll get some estimates here tomorrow and meanwhile email these fabric guys in the off chance they have some close by