Window Vent Mod- Louvered Ventilators- Fabrication Lessons Learned

[dhaig]

I recently undertook fabrication of a set of louvered ventilators for the three side windows of our LEII, following the excellent design posted by @csevel.  I want to share some lessons learned for others who may want to fabricate a set for their Ollies.

 

The window vent consists of two main parts, a purchased louver ventilator and a custom made acrylic mounting plate, shaped to fit a partial window opening, into which the louver is mounted.

 

I executed the fabrication a bit differently from @csevel.  Since I wanted to produce a set of three louvered ventilators, I made a template using 1/4" medium density fiberboard (MDF) for the mounting plate.  I, too, used one of the window screens as a guide for the edge contours of the template to match the sliding windows and frames.  The final mounting plate template is 16-3/8" tall and 6-5/8" wide at the midpoint.  The rectangular opening is 3-½" wide x 12-1/16" tall.

 

After tracing the screen contour for the vertical edges of the template, I clamped the window screen to the MDF and used the screen as a template for my router to follow, to cut the shape.

 

Cutting external edges of MDF template

 

I had purchased the White Water Plastic 5-Slotted Louvered Ventilators from Amazon, although they are now shown as unavailable.  I recommend searching for other sources, such as West Marine.  It appears the same product is sold under multiple brand names.

 

I used one of the purchased louvered ventilators to determine the size of the rectangular opening required in my MDF template and centered the outline for the opening.  Note the rear of the louvered ventilator is tapered, so the opening needs to be large enough to accept the entire rear projection through the MDF mounting plate template, with the flange of the louver meeting the mounting plate.  The rear projection also has two reinforcing ribs on each of the long sides and one each on top and bottom, which require notching the sides of the opening for clearance.

 

To cut out the rectangular opening in the MDF template, I first tried to use my router, but found it very difficult to control the router and tried various guides, unsuccessfully.  Achieving accurate cuts freehand with the router was also very difficult.  In retrospect, using a router table to cut the opening rectangle would not be too difficult if done with straight outer edges, prior to cutting the outer edge curves.

 

Frustrated by my lack of skill with the router, I switched to using a scroll saw to cut the rectangular opening in the mounting plate.  This requires drilling a starter hole inside the rectangle, then inserting the scroll saw blade.  

The scroll saw proved very useful in making accurate cuts to make the MDF template.  I tried to cut the rectangular opening as accurately as possible, which was relatively easy to do.  If a scroll saw is not available, I recommend using a high quality hand held jigsaw as another option.

 

After cutting the outer curved edges and rectangular opening in the template, I sanded the edges smooth and inserted one of the louvers into the template to test for fit.  I used blue painter's tape to hold the louver in the template while testing the fit in the window opening.

 

Test fitting the MDF template and louver

I inserted the MDF template and louver into the window opening to verify the curved side abutting the window fit closely, with as small a gap as possible.  I made slight adjustments to the template with a belt sander mounted upside down on a work table.  I also verified the template could be inserted into the window track while inside the trailer, without  requiring removal of the window shades or screen.  While inside the trailer, position the mounting plate and louver through the window opening and tilt the top topward the upper screen track. The mounting plate is first inserted into the upper track of the screen, then placing the bottom of the plate into the lower window track, then moving the top of the mounting plate from the screen track into the window track. Sounds confusing, but works easily after a few tries.

 

When the mounting plate template is inserted into the window track and pressed against the window edge, there is space above and below the plate and the window track.  Once the mounting plate template is in the window track, it should be lifted slightly as the window is moved to shut against the plate.  This should result in the curved edges of the mounting plate mating closely with the curved outer edge of the window, top and bottom.  Closing the window against the mounting plate secures it in place, seated against the vertical edge of the track and the edge of the window. 

 

After several trial fittings and minor adjustments to the template, I was satisfied the template mounting plate would fit snugly to minimize the chance of water leaking in at the junction with the window.  I did all of the trial fittings on the street side window above the bed.  Only then did I test the template in the other two similar windows, which is when noticed the edges of the three windows are not uniform.  The street side aft window had some black sealant projecting from between the two panes of glass.  On the other windows, the sealant material does not extend from the edge of the two panes of glass.  When fitted against the outer pane of glass in each of the three windows, the mounting plate template proved to be a snug fit, when carefully inserted.

 

As a final test of the fitment of the mounting plate template, I tested to verify each of the window screens would close.  Initially, they would not.  The rear of the louver ventilator projects one inch from the rear of the front flange, causing interference with the screen and preventing its closure.  Since the louvers do not have any screen built in to prevent entry of insects, operation of the standard window screens is essential.

 

@csevel indicated her screens would close with the louver in place.  I suspect my louvers and hers may not be exactly the same depth.  Or, since our trailers are five model years apart, there may be differences in our windows.

 

My solution to resolve the screen interference issue was to reduce the rear projection of the louver ventilator 3/8" by:

• Removing 1/8" off the rear projection of the louver ventilators using a table saw;
• Fabricating spacers from 1/4" thick acrylic sheet to insert between the mounting plate and the front flange of the louver ventilators.

 

Removal of 1/8" of depth from louver ventilator

 

1/4" Spacers dry fitted to rear of front flange of louvered ventilators

In the photo above, all three louvered ventilators have had their depth reduced by 1/8" and 1/4" spacers dry fitted prior to cementing in place.  The spacers are 9/16" wide, surrounding the rear projection of the louver ventilators. (The protective paper coating is still in place on the spacers in the photo.)

 

Side view of spacers bonded to rear of the flange of a louver ventilator

 

The spacers were bonded to the rear of the flange using acrylic cement applied using a small application bottle with a needle applicator (from small box in photo below).  After dry fitting, I cemented the spacers to the louvers, starting with the top and bottom, while the side spacers were in place loose, without cement.  After the top and bottom spacers were firmly cemented, I cemented the side pieces.  I found using spring clamps to hold the spacer pieces in place worked well while the cement set.

 

 

I test fitted the louver ventilators inserted into the template mounting plate to verify the interference problem with the screen was resolved.  The screens cleared with very little space to spare.

 

Fabrication of Mounting Plates

Having completed the mounting plate template, I next made a copy of the template, also from 1/4" MDF, as a backup in the event I damaged the master template.  Making a copy also served as a dry run for routing the acrylic sheet.

 

Using double sided woodworking tape. I fastened the template copy to a sheet of 1/8" black acrylic sheet, in preparation for cutting the first mounting plate.  (Use the woodworking tape sparingly- 6 pieces 1 inch in length is sufficient.  Otherwise, it can be difficult to remove, with adhesive left behind.)

 

MDF template on acrylic for routing

 

From experimentation cutting scrap acrylic sheet with the router, I had found the router bit would quickly melt the acrylic sheet.  To avoid melting the acrylic sheet, I removed the excess acrylic material from around the template and the rectangular cutout, leaving only 1/16" to 1/8" of material to be removed by the router bit.  I was then able to obtain smooth edges following the template for final trimming with the router.

 

With the template attached by woodworkers tape to the 1/8" acrylic sheet, I used the scroll saw to cut the acrylic, keeping the saw kerf 1/16" to 1/8" away from the template.  This freed the first piece of acrylic from the larger sheet and removed excess acrylic material from around the template.  

 

I mounted my router, with a 1/2" flush trimming bit, to a small router table.  I then proceeded to trim the remaining acrylic sheet from around the template, both the outside edges and the rectangular cutout.  After routing the first mounting plate, I repeated the same steps two more times, attaching the template to the acrylic sheet, trimming away the excess material using the scroll saw, then making the finish trimming using the router mounting in the table.  When I had routed all three mounting plates, I lightly sanded the edges of the acrylic mounting plates to remove the sharp edges.

 

Assembly of louver ventilators to mounting plates

The louver ventilators with spacers attached are dry fitted to the mounting plates.  Once satisfactory fit is verified, the parts are ready to be cemented using the acrylic cement.  

 

NOTE: The louver ventilators for the Street side windows are oriented opposite those for use on the Curb side.  Position the mounting plates properly to abut the windows and insert the louver ventilators with their louvers on the outside and the louver openings facing down.

 

I found it easiest to start by cementing one of the short ends of the louver ventilators to the mounting plate, using a couple of spring clamps to hold the parts together until the cement formed a firm bond, which takes about 5 minutes.  Proceed to cement successive sides of the louver ventilator to the mounting plate, one side at a time, applying spring clamps until the cement cures.  Use the needle applicator to apply cement at the intersections of the parts.  Allow the cemented parts to cure overnight.  The acrylic cement is very effective at welding the acrylic parts together, producing a very rigid assembly.

 

Completed set of louvered ventilators and mounting plates

 

After assembly, I added the same rubber edge trim recommended by @csevel to the edge of the mounting plate which meets the window edge.  This trim seems to conform well to close any gaps between the windows and the mounting plates.

 

The completed units are quite rigid and nest reasonably well.  I set the width at 6-5/8" for two reasons:

• To yield three mounting plates from a 24" x 24" sheet of acrylic
• To keep the mounting plates and louvers as small as possible to facilitate storage in the trailer.

 

I made a pouch to contain the louver ventilators to make it easier to store them without concern for damage to them or to other parts of the trailer.  I had leftover car headliner material, which is relatively thin, with a foam backing, to which Velcro straps readily attach.

 

Summary

This project, which I first thought rather simple, provided several challenges.  I spent much more time than expected to achieve an acceptable result.  Given the extended drought and high temperatures in Texas, I have not had an opportunity to test the effectiveness of the vents, nor how well they keep rain out.  In a week we depart for a two and a half week trip to Colorado to photograph fall color.  I expect we will encounter some test conditions in the mountains.

 

I hope this information is useful.  Please feel free to contact me with questions.

 

Regards, Don

[Mike and Carol]

We’ll done!  Thanks for the detailed post.  Mike

[BBL]

I have seen several posts and comments about venting during rain and solutions around it.  As a new owner in waiting, I have to ask; is this really a problem?

I mean, when it rains is there an issue with getting ventilation into the trailer without soaking everything?  It is starting to concern me.  I also have to say, when we were first looking at the Oliver I noticed the sliding windows and commented how our current (Airstream) windows were awning windows, i.e. they pushed out from the bottom and how much we loved having the windows open in the rain.

Every major manufacturer has moved to awning-style windows and I am sure it is for a good reason.

Someone please tell me this is a non-issue and more of a nice-to-have.

Thanks - 

Brian

[dewdev]

We manually open the Maxx Fan vent hood slightly (without running the fan) so there is some venting during rain storms.

Seems to work for us but I must say that we have never been at the Ollie during rain storms that last all day.

[bhncb]

37 minutes ago, Brian and Brandelyne said:

Someone please tell me this is a non-issue

I haven’t found it to be but:

In 2018 when I ordered, the awnings were manual and, having the additional “street-side” awning, my sop is to extend both 12-16 inches. This is enough to provide both rain protection and midday shade.

Wind damage has not been an issue and I’m typically where much of the “agriculture” theses days has three-blades.

[Mike and Carol]

1 hour ago, Brian and Brandelyne said:

… I have to ask; is this really a problem?

It’s not an issue.  We have the maxxfan open almost always as well as the bath fan.  That provides ventilation.  Sometimes during really hard rains we shut the bath fan because some of the rain bouncing off the roof can make the bath floor damp.  If it isn’t a hard rain, keeping a window cracked is something else we do.  Mike

[GraniteStaters]

5 hours ago, Brian and Brandelyne said:

I have seen several posts and comments about venting during rain and solutions around it.  As a new owner in waiting, I have to ask; is this really a problem?

I mean, when it rains is there an issue with getting ventilation into the trailer without soaking everything?  It is starting to concern me.  I also have to say, when we were first looking at the Oliver I noticed the sliding windows and commented how our current (Airstream) windows were awning windows, i.e. they pushed out from the bottom and how much we loved having the windows open in the rain.

Every major manufacturer has moved to awning-style windows and I am sure it is for a good reason.

Someone please tell me this is a non-issue and more of a nice-to-have.

Thanks - 

Brian

I'd like to be able to keep the windows open on humid, rainy days but we do OK by keeping the main cabin fan open and running and opening the bathroom vent.  Often we can open the rear window because it is straight, not slanted, so the rain doesn't come in as much as the side windows. Paula

 

[dhaig]

6 hours ago, Brian and Brandelyne said:

I have seen several posts and comments about venting during rain and solutions around it.  As a new owner in waiting, I have to ask; is this really a problem?

I mean, when it rains is there an issue with getting ventilation into the trailer without soaking everything?  It is starting to concern me.  I also have to say, when we were first looking at the Oliver I noticed the sliding windows and commented how our current (Airstream) windows were awning windows, i.e. they pushed out from the bottom and how much we loved having the windows open in the rain.

Every major manufacturer has moved to awning-style windows and I am sure it is for a good reason.

Someone please tell me this is a non-issue and more of a nice-to-have.

Thanks - 

Brian

@Brian and Brandelyne

As you have likely seen in the comments, ventilation during rain is an issue to some owners and not to others.  I offer the follow comments based on our experience owning our LEII since mid-February.  Since I have expended my time and about $50 on the louvered ventilators, you can count me among the owners who want better ventilation capabilities.

The week we took delivery there was constant, heavy rain in Hohenwald and surround areas.  We also encountered heavy rains between Hohenwald and Dallas during our 10 day return trip.  Anytime there is more than light rain water can readily enter partially open sliding windows.  There were several nights when we had opened the windows slightly open (3-4 inches) for ventilation and were awakened by heavy rain and water entering the cabin through the open windows.  This is especially noticeable when the open window is above the bed where one is sleeping.

We have only a curb side awning, which I have tried extending 1-½ to 2 feet when rain is falling (or expected) to shelter the partially open curb side window.  When the awning is  extended this short distance it generally prevents rain from entering the partially open window.  However, a large quantity of water accumulates in the awning.  I had expected the rainwater to run off the ends of the awning, but this was not so.  I was alarmed to see how much water was held by the awning and became concerned it would damage the awning.  Our awning also has a motion sensor, which will automatically retract the awning if winds are moving it.  We have had the awning retract during thunderstorms.

During another trip, we were camping in western NC, near the Blue Ridge Parkway.  We had left our dog in the trailer while we went hiking, as she was not permitted on the trails.  Rain was not expected and temperatures were mild, so we left windows partially open on both sides of the trailer.  About 2 hours later an intense thunderstorm appeared.  We had small umbrellas with us, but still got rather wet.  Upon returning to the trailer, we found wet beds from rain entering the windows.  On the same trip, we were camping at Paris Mountain SP, near Greenville, SC.  We received heavy rain a couple of nights we were there.  So we have become cautious about having windows left partially open.

I had read many comments on the forum about the need for ventilation to prevent condensation.  We have used the Maxx fan and the bathroom fan to help circulate air in the trailer.  When operating these fans, fresh air must enter from somewhere and the trailer has few places to admit any significant volume of outside air, hence opening windows becomes necessary.

Consequently, not being a keen on sleeping in a wet bed, I was very happy to see the forum post by @csevel with her clever solution for providing ventilation, especially during rainfall.  Thus, I decided to follow the louver ventilator design to have a solution available for a problem I expect to encounter regularly.  The cost was relatively low and  the solution appears likely to improve ventilation, with lower risk of rain water entering the cabin..

I agree that the sliding windows on our Oliver are more likely to admit rain water when opened than are awning type windows, which tilt out from the bottom.  The tilt of our sliding windows further aggravates the problem, as there is no protection from rain falling directly on the lower part of the windows.  Also, I have read many forum posts about the need to keep the weep holes along the lower window track clear to prevent water accumulating in the window tracks and spilling into the cabin.  I have also read more than a few forum posts about various over window awning/hood designs by Oliver owners.  I suspect many of these designs result from experiences similar to ours.  There are also many forum posts about Oliver owners installing EZ Gutters over the window, as I also recently installed.  I can think of no reason to install these gutters over the windows than to reduce the amount of rain flowing over the windows.

I was aware of the vulnerability of the Oliver sliding windows to water entry prior to placing our order.  The risk seemed manageable.  I was also aware through my due diligence research before our Oliver purchase of very significant water leakage problems common to most RVs due to structural integrity issues.  The Oliver construction, with no major seams on the roof appeared to me likely to prevent most of the water leakage issues experience with other brands.  I have found reports of water leaks in Oliver trailers to be quite rare.  If Oliver offered a choice of window styles, sliding or awning, I would likely choose awning, assuming that option was also double pane insulated glass, which I understand most are not.  I am not aware of any Oliver trailers ever having awning windows.  This was not a deterrent to our ordering an Oliver trailer.  We are happy with our purchase.

Regards, Don

[SeaDawg]

Our old school 2008 has one awning window, in the back (emergency egress window.) No longer available. 

When we have a torrential downpour,  we close the windows (even the ones with the old louvered vents), open the bath vent and hooded fantastic vent, and run the big fan, on higher than normal.  

We had about 12 inches of rain in 24 hours last summer, one day. We survived,  and the trailer was dry.

In lighter rains, well leave the manual awning extended a bit, and open the two windows we have with louvered vents. 

In our experience over the many  years, with a number of campers,, awning windows are not a total  panacea,  but they can help in certain conditions.  As can adjustment of the jacks, to send the rain to the closed window side, or to the rear, etc. Depending on how you are oriented to the storm, and wind driven rain. Most awning windows today are acrylic, European style,, prone to scratching and clouding/etching, and air leakage. 

I never worry about the marine bath, if I leave the bath vent and bath window open. If it gets wet, a microfiber towel solves everything, quickly. 

 

 

[AlbertNTerri]

in most rain we've encountered it usually only affects one side and not the other, we open the "dry" side and the bathroom window, turn the fans on and haven't had a problem. I do like the louvers I've seen in the forum and will probably make a set at some point, but it's not a real high priority since there always seems to be a dry side and when there's not you can always open the bath window and just dry off what little comes in after the storm. 

[BBL]

@dhaig Don - First, let me say, in no way was I implying that what you were doing was unnecessary. You work, as well as the original poster’s, was nothing short of amazing. What a great idea and well executed. I especially like the pouch you created.

Like you, I have owned my share of trailers and have, and still am, doing my due-diligence pre-purchase to my LE II.  Our awning windows in the Airstream certainly were not perfect and needed to be closed in certain conditions and because of where our Fantastic Fan was located, we couldn’t get a shroud over it. The Airstream service center tried two different brands and they wouldn’t fit because it was installed too close to the antenna. This was after we were assured we could get one installed and made the trip to the service center. Needless to say, that was disappointing. At least it had a water sensor that would close when it rained.

I would also like to thank you for such a well documented post and reply to my concerns. Not everyone would take the time to thoroughly explain the conditions that you have experienced to want to implement this work-around.

As @SeaDawg mentioned, the popular European design awning windows are acrylic and will scratch and cloud up but they are double pane and very well insulated.

We have experienced many different Forums (off-reading, Amateur Radio, Airstream, etc) and this has been the most helpful group of people I have ever experienced.

Thank you for keeping the dialog going in a kind, professional manner.

Regards,

Brian

[Guest]

1 hour ago, Brian and Brandelyne said:

the popular European design awning windows are acrylic and will scratch and cloud up but they are double pane and very well insulated.

This has been our experience. We had the double paned acrylic windows in our Black Series HQ15. We had a lot of thin delicate scratches on the windows. I definitely prefer double paned glass windows. 

[Katjo]

On 9/22/2022 at 10:16 AM, Brian and Brandelyne said:

I have seen several posts and comments about venting during rain and solutions around it.  As a new owner in waiting, I have to ask; is this really a problem?

I mean, when it rains is there an issue with getting ventilation into the trailer without soaking everything?  It is starting to concern me.  I also have to say, when we were first looking at the Oliver I noticed the sliding windows and commented how our current (Airstream) windows were awning windows, i.e. they pushed out from the bottom and how much we loved having the windows open in the rain.

Every major manufacturer has moved to awning-style windows and I am sure it is for a good reason.

Someone please tell me this is a non-issue and more of a nice-to-have.

Thanks - 

Brian

We’ve never had any issue. We leave our Maxx Air fan open (even in heavy rain storms) and that’s been suffice. 

[dhaig]

@Brian and Brandelyne, thanks for the kind comments.  I was concerned that I had caused you alarm about the degree of the ventilation problem.  I don't think it so serious it should cause concern over your pending delivery.  A bit of a nuisance with available solutions.

I apparently gave you the impression I have owned multiple trailers.  I have not.  Our Oliver is our first RV.  Not having had any prior experience with RVs, I did a lot of research before selecting our Oliver.  A significant factor in our selection of our LEII was the information provided on this owners' forum.  The postings appeared to me authentic, with no apparent influence by the Oliver organization, including postings of both criticism and praise of the product.  The participants in this forum have been very helpful in my RV education.  I was also quite impressed by their ingenuity in making improvements and modifications to their trailers.  I try to return the favor.

Don

[BBL]

@dhaig Don - You did not cause undue concern. When I am making a large purchase like this I tend to look into everything I can find and determine if it is actually an “issue” or it is something that just has to be dealt with in any number of ways. If I find something that is a design flaw, I would expect it to be rectified by a re-design and others may have to make changes on their own.  Your extensive knowledge and research of the RV industry probably led to my assumption you had owned more than one RV or trailer.  Enough of that though…

Where are you in North Texas?  I was stationed in OKC, OK for 10 years and made quite a few friends in N. TX, mostly Dallas and out to Midlothian, TX. My friends daughter went to U N TX around the Denton area. I like the area but way too crowded for me.

From the looks of your map, you tend to travel in the SE US. We are in TN, about two hours from Hohenwald so that makes it nice shopping for the Oliver.

Take care, safe travels,

Brian

[hobo]

Would love to see some pics of the vents installed.

Also, sounds as though there are enough variables in the trailer windows that mass production of these vents is not a viable option.  Seems to be trailer specific and perhaps even window specific for proper fitment.

Am I correct on this point?

 

[John Dehne]

Nice job! 
I was thing of installing a new door window with a 50% slider glass and a screen to ventilate during a rain. It’s the only vertical window we have and I wouldn’t  mind a little rain water by the door during a rain.  Started searching for a manufacturer. 

[dhaig]

@hobo, my apologies.  Please see photos below.  Note the screens are not in the fully closed position in some of the photos. 

As I mentioned, there was some variability on the edges of the sliding windows, however, the rubber edge trim conforms reasonably well to close small gaps between the mounting plates and windows.  How effective this is in preventing water penetration remains to be seen.  I anticipate we will have opportunities to conduct field tests during our trip to Colorado over the next 2-½ weeks.

I would not rule out the possibility for the vents to be mass produced, but I have not had any opportunity to test them across model years of LEII trailers.  The most critical dimension to control is the depth to which the rear of the louver vent  projects inward, toward the sliding screen, before there is interference.  

There is space above and below the mounting plates.  The vertical position of mounting plates is determined by the match of the upper and lower curves of the mounting plate fit with that of the windows.  I have no idea how much dimensional variation there might be in windows installed by Oliver over the model years.