*Not a definitive answer - a few UMH people have direct, hands-on experience with this (hopefully they may chime in).*

The following 3x plots may be helpful for your 2nd question: MoWITT vs TARP-predicted **hf** (forced convection, in W/m2.K ... Y-axis) for very smooth (windward) surfaces, as a function of local **Vz** (window height, up to 60m). Assuming *default* E+ weather station conditions (height = 10m, exponent 0.14, boundary layer thickness 270m), vs local building conditions similar to the original studies, further discussed here (exponent 0.22, boundary layer thickness 370m).

At *low* wind speeds at the weather station (Vmet 2m/s; Vz 1.4m/s @10m), IMHO it's fine to rely on MoWITT up to 60m: it's more conservative at lower heights (i.e. Yazdanian & Klems' thesis), and merges with TARP with increasing height. This is assuming a surface *perimeter/area* ratio of 3 for TARP (this has a significant impact on results).

At *slightly higher* wind speeds at the weather station (Vmet 2.5m/s; Vz 1.8m/s @10m), there's a crossover at ~20m. Hard to say if one should definitely switch to TARP above 20m, but it's giving you an idea of the range. Again, TARP's *perimeter/area* ratio is something to keep in mind (e.g. if it were **2** instead of **3**).

Finally, at *higher* wind speeds at the weather station (Vmet 3m/s; Vz 2.2m/s @10m), the crossover is around 10m (roughly what Yazdanian & Klems would consider low-rise residential buildings, their target building type). The discrepancy between predictions starts to be somewhat significant at greater window heights (without even considering TARP's *perimeter/area* ratio). In my neck of the woods, average winter wind speeds (weather station) are around 4m/s. I'd likely avoid MoWITT above 4 or 5 stories. But I'm unsure what the alternative is really, given TARP's sensitivity to the *perimeter/area* ratio. I may have to take a deeper dive, as I can't get my head around this ratio when it comes to fully-glazed, 10-storey buildings with silicon structural joints.

Long story short, it would seem to depend strongly on expected wind speeds. But low-rise, 3-storey residential buildings definitely seem to be the sweet spot for MoWITT.

I hesitate in answering your 1st question, as it's a bit confusing. Are you taking local wind speed measurements, and attempting to estimate **hf** for glazed surfaces nearby? If so, I'd rely on the initial local wind speed equation while characterizing your local wind environment. I may be misunderstanding the question ...